saj_specs

SPECIFICATION FOR PIPEWORKS

SPECIFICATION SAJH WS / PW / 001 (Rev.1.0 / 06.2007)

QUALITY ASSURANCE DEPARTMENT SAJ HOLDINGS SDN. BHD.


CONTENTS PAGE NO. 1.0 GENERAL 1

1.1 Order for Pipes and Specials 1 1.2 Approvals 1 1.3 Hauling and Handling 1 1.4 Records of Pipes Supplied 2 1.5 Prospecting 2 1.6 Pipe Alignment and Cover 3 1.7 Pipelaying in Grounds with High Water Table 4 1.8 Dangers of Flotation 4 1.9 Temporary Cessation of Trench Excavation 4 1.10 Examination of Pipes and Fittings 4 1.11 Laying Pipes and Fittings 5 1.12 Specials 5 1.13 Testing Pipelines 5

1.13.1 General 5 2.0 MILD STEEL PIPES AND SPECIALS

2.1 General 7 2.2 Scope 7 2.3 Definition 7 2.4 Standards and Codes of Practice 7 2.5 Submissions 8 2.6 Pipes and Specials 9 2.7 Steel Pipes 9 2.8 Material, Workmanship and Welding Standards 11 2.9 Pipe Ends 12 2.10 Bends, Tees, Tapers, Etc. 13 2.11 Flanged Joints 13 2.12 Mechanical Couplings, Flange Adaptors and Expansion Joints 14 2.13 Pipes for Closing Lengths 15 2.14 Collars 15 2.15 Retaining Rings 15 2.16 Physical Testing 15 2.17 Works Hydraulic Testing 15 2.18 Ring Girders 16 2.19 Protection 16 2.20 Cleaning and Priming 16 2.21 External Coating 16 2.22 Wrapping 17 2.23 Inspection of External Pipe Coating 17 2.24 Painting Unwrapped Pipes and Specials 17 2.25 Spun Concrete Lining at Factory 17 2.26 Internal Protection at Pipe Ends 19 2.27 Pipework for Laying above Ground 19 2.28 End Protection 20 2.29 Examination of Steel Pipes 20 2.30 Low Friction Coating 20

SPECIFICATION FOR PIPEWORKS SAJH WS/PW/001 (Rev.1.0/06.2007) NO CHANGES ALLOWED WITHOUT THE PERMISSION OF QUALITY ASSURANCE DEPARTMENT OF SAJ HOLDINGS SDN BHD

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PAGE NO.

2.31 Handling 20 2.32 Repair of Lining and Sheathing of MS Pipes 21 2.33 Laying MS Pipe 22 2.34 Welding MS Pipe 23 2.35 Making Welded MS Pipe Joints 23 2.36 Air Testing of Welded MS Pipe Joints 24 2.37 Completion of Sheathing at Welded MS Pipe Joints 24 2.38 Completion of Internal Lining at Welded MS Pipe Joints 25 2.39 Testing MS Pipeline 25

2.39.1 Test Pressure 25 2.39.2 Leakage Testing 25

2.40 Protection in Transit 25 2.41 Notice of Deliveries 26 2.42 Pipe Dumps and Storage Yards 26 2.43 Inspection 26 2.44 Marking of Pipes and Specials 27 2.45 Measurement of Steel Pipes and Specials 27

3.0 DUCTILE IRON PIPES AND FITTINGS

3.1 General 28 3.2 Compliance with Standards 28 3.3 Process of Manufacture 28 3.4 Thickness and Diameters 28 3.5 Length of Straight Pipes 28 3.6 Tolerance on Dimensions 29 3.7 External Zinc Coating 29

3.7.1 General 29 3.7.2 Zinc Coating 29 3.7.3 Coating Characteristics 30 3.7.4 Verification Process 30 3.7.5 Repairs 30 3.7.6 Finishing Layer 31

3.8 External Coating of Pipes and Fittings 31 3.9 Internal Lining of Pipes and Fittings 31 3.10 Flexible Joints 32 3.11 Flanged Joints 32 3.12 Factory Hydrostatic Test 33 3.13 Connection to Pipes of Different Type 34 3.14 Cutting of Pipes 34 3.15 Packing 34 3.16 Polyethylene Sheathing 34 3.17 Handling 35 3.18 Laying DI Pipes 35 3.19 Protection Against Damage in Transit 36 3.20 Jointing Ductile Iron Pipe 36 3.21 Testing DI Pipelines 39

3.21.1 Test Pressure 39 3.21.2 Leakage Testing 39

3.22 Marking of Pipes and Fittings 39


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PAGE NO. 4.0 POLYETHYLENE (PE) PIPES AND FITTINGS

4.1 General 40 4.2 Scope 40 4.3 Interpretation 40 4.4 Manufacturing Process 41 4.5 Polyethylene Materials 41 4.6 Dimensions 41 4.7 Flanged Connections 42 4.8 Works Tests 43 4.9 Packing 43 4.10 Handling, Transportation and Storage 44

4.10.1 General 44 4.10.2 Handling and Transportation 44 4.10.3 Storage 45 4.10.4 Precautions 45

4.11 Electrofusion Couplers and Tapping Tees 45 4.12 PE Compression Fittings 47 4.13 Examination of Pipes and Fittings 47 4.14 Laying PE Pipes 47 4.15 Welding PE Pipes 48 4.16 Payment for PE Pipe Joints 52 4.17 Testing PE Pipelines 52 4.18 Markings 53

5.0 uPVC PIPES AND FITTINGS

5.1 General 54 5.2 Materials used in Manufacture 54 5.3 Colour 54 5.4 Classification 55 5.5 Thickness and Diameter 55 5.6 Tolerance and Dimensions 55 5.7 Length 57 5.8 Appearance 57 5.9 Joints 57 5.10 Pipe Seal 58 5.11 Test Requirements 58

5.11.1 Obligations 58 5.11.2 Routine Tests 58 5.11.3 Type Tests 58 5.11.4 Sampling 59

5.12 Routine Tests 60 5.12.1 Heat Reversion Tests on uPVC Pipes 60 5.12.2 Resistance to Acetone Test on uPVC Pipes 60 5.12.3 Factory Hydrostatic Test on uPVC Pipes 60 5.12.4 Impact Strength Test at 20 degrees C on uPVC Pipes 60

5.13 Compliance 61 5.14 Method of Rejection 61 5.15 Marking of Pipes and Fittings 61 5.16 Test Certificates 62 5.17 Delivery 62


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PAGE NO. 6.0 PIPELAYING

6.1 Closing Lengths 63 6.2 Pipe Cutting 63 6.3 Welding Personnel 63 6.4 Making Joints with Mechanical Couplings and Flange Adaptors 64 6.5 Making Flanged Joints 64 6.6 Measurement of DI, Cast Iron, Steel, PE Pipes and Fittings 65 6.7 Concrete Protection to Pipes 65 6.8 Thrust and Anchor Blocks 65 6.9 Valve Chambers 66 6.10 Crossing Over Streams, Culvert and Rivers 66 6.11 Payment for Pressure Testing Pipelines and Specials 66 6.12 Sterilising and Flushing Pipelines 67 6.13 Payment for Sterilising and Flushing Pipelines 67 6.14 Payment for Road Restoration 67 6.15 Clearing Up 68 6.16 Indicator Posts 68 6.17 Painting Pipework and Valves in Chambers 68 6.18 Painting Pipework Above Ground 68 6.19 Disposal of Surplus Goods 69 6.20 Payment of Fees to Authorities 69

7.0 PIPE JACKING

7.1 General 70 7.2 Tender Submission 70 7.3 Surface Reinstatement in Road Verges, Fields, etc. 71 7.4 Prospecting 72 7.5 Performance Requirements 72 7.6 Approval of Owner 72 7.7 Jacking Operation 73 7.8 Safety 74 7.9 Design of the Jacking Pipes 75 7.10 Laying and Connections of Pipeline in Jacked Reinforced

Concrete Pipes Sleeve 76 7.11 Alternative Method of Pipe Jacking 77 8.0 EARTHWORKS

8.1 Definitions 78 8.2 Levels to be Recorded 78 8.3 Explosives and Blasting 78 8.4 Disposal of Materials 79 8.5 Excess Excavation to be Made Good 80 8.6 Site Clearance 80 8.7 Trees 80 8.8 Stumps 80 8.9 Measurement of Site Clearance 80 8.10 Stripping Topsoil 80 8.11 General Excavation 81 8.12 Trench Excavation 81


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PAGE NO. 8.13 Trench Excavation in Roads, Road Shoulders and

Footpaths 82 8.14 Trench Excavation in Fields, etc. 83 8.15 Rock and Other Materials in Excavations 83 8.16 Supporting Excavation 83 8.17 Trimming Excavations 84 8.18 Inspection of Excavation 84 8.19 Filling to Embankments and Backfilling to General Excavation 84 8.20 Trenches Not to be Left Open 85 8.21 Refilling Trench Excavation 85 8.22 Soft Refill Material – Special Measures 87 8.23 Temporary Spoil Tips on the Site 87 8.24 Treatment of Material from Excavation 87 8.25 Surface Reinstatement in Road Verges, Fields, etc. 88 8.26 Works in Roads and Road Reserves 88 8.27 Surface Reinstatement in Roads and Footpaths 89 8.28 Payment for Road Restoration 89 8.29 Other Structures in the Pipeline 90 8.30 Land Drains 90 8.31 Care of Existing Services 91 8.32 Hedges, Fences and Walls 92 8.33 Crossing Watercourses, etc. 92 8.34 Measurement of General Excavation 92 8.35 Measurement of Trench Excavation 93 8.36 Measurement of Filling for Embankment 95 8.37 Payment for Trench Excavation and Restoration 95 8.38 Top Soiling 95 8.39 Turfing 95 8.40 Measurement of Top Soiling and Turfing 96 8.41 Payment for Turfing 96 8.42 Payment of Fees to Authorities 96

9.0 PILING

9.1 General 98 9.1.1 Ground Conditions 98 9.1.2 Setting Out 98 9.1.3 Piling Equipment 99 9.1.4 Programme 99 9.1.5 Pile driving 100 9.1.6 Preliminary and Working Test Piles 101 9.1.7 Load Tests 101 9.1.8 Piling Personnel 101 9.1.9 Piling Records 102

9.2 Precast Reinforced Concrete Piles 102

9.2.1 General 102 9.2.2 Pile Casting 102 9.2.3 Curing, Stripping and Stacking 103 9.2.4 Handling Storage and Transport of Piles 103 9.2.5 Pitching and Driving 103


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PAGE NO. 9.2.6 Plant for Pile Driving 104 9.2.7 Measuring Pile Set 104 9.2.8 Extending Piles 105 9.2.9 Preparation of Pile Heads 105 9.2.10 Load Tests 105

9.3 Treated Timber Piles 106

9.3.1 General 106 9.3.2 Treatment of Piles 106 9.3.3 Delivery and Stacking of Piles 106 9.3.4 Pile Driving and Jointing 107 9.3.5 Load Tests 107

9.4 Pile Testing 108

9.4.1 General 108 9.4.2 Test Load and Kentledge 108 9.4.3 Settlement Measurement 108 9.4.4 Equipment and Personnel for Load Test 109 9.4.5 Procedure of Testing 109 9.4.6 Records of Test 110 9.4.7 Interpretation of Test Results 110

9.5 Measurement of Piles and Piling 110

10.0 ROADWORKS

10.1 Preparation of Formation to Receive Road 112 10.2 Earth Subgrade 112 10.3 Subgrade of Rock 112 10.4 Pavement Thickness 113 10.5 Sub-base Materials 113 10.6 Alternative Sub-base 114 10.7 Compaction of Sub-base 114 10.8 Road-base Materials 115 10.9 Laying and Compaction of Roadbase 115 10.10 Finished Surface 117 10.11 Definition and Requirements Associated with Table 10.1 117 10.12 General 118 10.13 Cutback Bitumen 118 10.14 Bitumen Emulsion 118 10.15 Storage, Handling and Heating-of Bitumen 118 10.16 Depot Tray Test 118 10.17 Material 119 10.18 Surface Preparation 119 10.19 Application of Prime Coat 119 10.20 Spraying Procedure 120 10.21 Protection of Prime Coat 120 10.22 Aggregate, Binder and Composition 120 10.23 Mixing 122 10.24 Transport 123 10.25 Sampling and Testing 123 10.26 Bitumen Macadam Layer Thickness and Tolerance 123


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PAGE NO. 10.27 Laying of Bitumen Macadam 124 10.28 Bituminous Tack Coat 124 10.29 Joints 124 10.30 Laying Around Manhole Covers 125 10.31 Compaction 125 10.32 Road Shoulders 125 10.33 Shoulder Base Selected Fill Grading 126 10.34 Lateral Shoulder Sub-drains 126 10.35 Refilling of Excavated Pipe Trenches for Roadways 126 10.36 Notes Relating to Table 10.1 126 10.37 Geotextile Filter Membrane 128 10.38 Storage of Geotextile Filter Membrane 129 10.39 Laying and Spreading Over the Geotextile Filter Membrane 129 10.40 Laterite Pavement 135

10.40.1 Preparation of Formation to Receive Road Pavement 135

10.40.2 Pavement Material 135 10.40.3 Spreading and Laying the Laterite Pavement 136 10.40.4 Compaction 136 10.40.5 Rectification of Surface 137

11.0 BRICKLAYER

11.1 Bricks 138 11.2 Cement 138 11.3 Sand for Mortar 138 11.4 Water 139 11.5 Mortar 139 11.6 Mixing Mortar 139 11.7 Brick Laying 139 11.8 Half-Brick Walls 140 11.9 Facing Brickwork 140 11.10 Damp Proof Course 140 11.11 Lintels 140 11.12 Building In 140 11.13 Scaffolding 141 11.14 Valve Chambers and Manholes 141 11.15 Payment for Brickwork 141

12.0 STEEL AND METAL WORKS

12.1 Structural Steel Work 142 12.2 Bolts and Nuts 142 12.3 Steel Chequered Plate 142 12.4 Handrailing 143 12.5 Ladder 143 12.6 Step Irons 143 12.7 Fencing 143 12.8 Aluminium Structures and Sections 144 12.9 Galvanised Metals 144 12.10 Dissimilar Metals 145


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PAGE NO. 12.11 Rain Water Pipes 145 12.12 Open Mesh Flooring 145 12.13 Manhole Covers, Surface Boxes, etc. 145

SECTION 1.0 - GENERAL



1.0 GENERAL The Contractor shall supply all the pipes and specials required unless

otherwise specified and construct and complete the pipeline and all associated works as specified and included herein under the Contract.

All welding materials, welding equipment, butt and electro fusion equipments,

clamps, steel moulds, priming solution, bitumen compound and approved bitumen wrapping tapes or similar material for completing the pipelaying works shall be deemed to be included in the rates of pipelaying unless specific items are provided in the Bill of Quantities.

1.1 Order for Pipes and Specials The quantities of the items in the Bill of Quantities are only approximate and

shall be ascertained by the Contractor after the pipeline profiles are determined by a survey carried out in accordance with Clause 8.2 of earthworks.

Where a pipe special is to be used for connection to existing works, the

Contractor shall purchase the special after he has ascertained the existing pipe diameter, flange and other details at the exact location where it is to be laid.

Excess order of pipes and fittings shall be the responsibility of the Contractor

and shall be at his own cost. 1.2 Approvals

All pipes/valves/joints/fittings/couplings/adaptors shall undergo for SAJH approval procedure by the QA Department and shall have either ISO Quality Standards Approval, SIRIM/IKRAM or other recognized standard approving authority.

1.3 Hauling and Handling

Great care shall be exercised to ensure that the pipes and specials are not subject to any kind of shock or sudden load during hauling and handling. Attention is drawn to the Contractor that thin wall pipes, defined as pipes with a diameter/plate thickness ratio greater than 125, shall be so handled, stored and transported as to prevent distortion or damage to the pipes and shall not be moved in any manner involving rotation of the pipe about the longitudinal pipe axis. Thin wall pipes during delivery and when in transit around the Site shall be supported on three rubber covered saddles shaped to give at least 90o circumferential support and shall be firmly held in position at each saddles by straps tightened by turnbuckles in such a manner that the external coating is not damaged. One saddle shall be at the centre of the pipe length and the other two shall each be positioned at a distance one-fifth of the pipe length from each end of the pipe.


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Thin wall pipes in temporary storage or strung out along the pipeline reservoir routes shall be supported on hessian bags filled with fine sawdust straw or similar and shaped so as to give continuous support under at least 40-50 o of the circumference. The positions of supports shall be the same as that for pipes during transit. The underside of the pipes shall be kept clear of the ground by at least 300 mm. All pipes and pipe specials shall be lifted by means of reinforced canvas slings. The pipes shall be lifted by two reinforced canvas slings at least 300 mm wide suspended from a lifting beam so that the slings are positioned approximately one-fifth of the pipe length from each end of the pipe. On no account shall the pipes and specials be dropped or let fall onto the ground and under no circumstances shall the pipes or pipe specials be lifted by means of hooks to the ends of pipes and pipe specials. The Contractor shall be deemed to have allowed the cost of providing the above necessary measures in the Contract Rates for hauling and laying. Any damage to or loss of materials shall be made good, or the damaged or lost materials replaced, by the Contractor at his own expense and if approved by the S.O. damaged materials shall be returned to the manufacturer for repair as directed by the S.O.

1.4 Records of Pipes Supplied The Contractor shall keep full and detailed records including item numbers,

size of each, and location of all pipes and specials which are: - (i) Inspected, taken over and transported to site (ii) Declared to be defective (iii) Used in the Works (iv) Cut, broken or removed from Site The Contractor shall keep such records continuously up to date, and shall

have them available for inspection by the S.O. at any reasonable time. 1.5 Prospecting The Contractor shall prospect for the position of buried or otherwise hidden

obstructions such as existing services, drains, pipes, cables, culverts, etc. Trial holes and exploration trenches to ascertain the exact positions of these shall be sunk, well ahead of pipelaying and excavation, in places where they are known or thought to be and elsewhere and these shall be backfilled with approved materials immediately and in any case not exceeding 24 hours and subsequently reinstated. Approved marker posts shall be erected to mark the position of all located services, drains, etc. and these shall not be removed until reinstatements has been completed. The S.O. shall instruct further prospecting if he is not satisfied with the sufficiency of the Contractor's prospecting.


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Where necessary the Contractor shall make arrangements prior to trench excavation proper for the temporary or permanent support or diversion of services, drains, etc, to the approval of the S.O. and the authority concerned. The full cost of prospecting shall be deemed to be included in the Contract Rates for pilot excavation.

Attention is drawn to Clauses concerning the responsibility of the

Contractor for the security of existing services. The Contractor shall be deemed to have allowed for the unavoidable delay

of the Works due to any obstruction he may encounter with the existing services and no claim for any extra costs on account of this will be allowed.

1.6 Pipe Alignment and Cover The routes of the pipelines shall be as shown on the Drawings or as directed

by the S.O. Pipes shall be laid to a minimum gradient of 1 on 500 unless otherwise

ordered by the S.O. Unless otherwise approved by the S.O. where the gradient of a pipeline is 1 on 20 or steeper, pipes shall be laid on an ascending gradient starting from washout (low point) and finishing at the air valve (high point).

Pipes shall be laid in straight lines on plan but curves of long radius shall be

obtained by deflecting MS pipes up to a maximum of 5° for spherical type and 2° for hemispherical type at welded slip joints and using short pipe lengths if necessary. For PE pipes the limitation for deflection does not apply.

Allowable angles of deflection for D.I. pipes are as follows: -

Nominal Diameter (mm) Allowable angle of deflection 80 - 200 5º 250 - 300 4º

Generally, for pipework of diameter below 1000 mm, the minimum cover to

the top of pipes shall be 1000 mm and at road crossings the minimum cover shall be 1500 mm unless otherwise specified. For pipework of diameter 1000 mm and above, the minimum cover to the top of pipes shall be 1500 mm unless otherwise shown on the Drawing.

Before commencing excavation the route of the pipeline shall be pegged

accurately. Strong sight rails shall be fixed and maintained at each change of direction and gradient, and at as many intermediate points not more than 35 metre apart as may be necessary. On these rails shall be marked the centre line and the level to which the pipe is to be laid.


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1.7 Pipelaying in Grounds with High Water Table The Contractor shall note that some parts of the pipelines will be laid in

grounds with high water table, especially in areas adjacent to the streams river crossings and ponds in the vicinity.

All costs for dewatering and keeping all the excavations and trenches dry for

the whole pipelaying work and in a safe manner during construction shall be deemed to be included in the Contract Rates except where specific provision is made in the Bill of Quantities.

1.8 Dangers of Flotation Although flotation of pipes in completely refilled trenches or of the

completed works will not occur, the Contractor's attention is particularly drawn to the danger of flotation of pipes laid in trenches left unrefilled and allowed to be flooded with water in the partially completed works.

The Contractor shall, immediately after pipes have been laid, jointed and

approved by the S.O., refill and compact excavated material to at least two thirds of the length of the pipe trench leaving only sufficient space unrefilled to allow for the completion of the external joint or fittings. Notwithstanding this, the Contractor shall make all necessary provision to avoid the flotation of any pipe during the construction stage.

Any damage caused by flotation of pipes, specials or fittings in unrefilled

trenches shall be made good to the satisfaction of the S.O. at the Contractor's own expense.

1.9 Temporary Cessation of Trench Excavation If in the opinion of the S.O. there is undue delay in :- (i) Refilling pipe trenches (ii) Jointing of PE pipes above ground to form string ready for laying. (iii) Laying and testing the pipelines (iv) Removing surplus material (v) General tidying up of areas where pipes have been laid (vi) Partial restoration or maintenance of surface the S.O. may order that no further trench excavation shall be opened until

the outstanding work has been carried out to his satisfaction and the Contractor shall have no ground for a claim against the Employer on this account.

1.10 Examination of Pipes and Fittings All pipes and specials shall be thoroughly cleaned and carefully examined

for cracks and flaws both internally and externally immediately prior to laying. Materials found to be damaged in any way shall be shown to the S.O. who will give instructions regarding remedial work or otherwise.


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1.11 Laying Pipes and Fittings All pipes and fittings shall be laid to the lines and levels shown on the

Drawings or as otherwise directed by the S.O. 1.12 Specials The approximate positions of all specials are shown on the Drawings. The

exact positions shall be determined on Site by the Contractor to the approval of the S.O.

1.13 Testing Pipelines 1.13.1 General After a length of the pipeline has been completed it shall be tested as a whole

against stop ends. The stop ends shall be supplied and fixed by the Contractor and shall be properly strutted to ensure that no movement can take place and they shall be of sufficient strength to withstand the full test pressure which is to be applied.

Testing shall be carried out over lengths of approximately (2) two kilometre

where possible or the full replacement length between washout or overcrossings but not against adjacent valves. Testing shall not be carried out until the backfilling of the pipe trenches except at the joints, have been completed. Backfilling at flexible joints shall be left uncompleted to facilitate inspection of these joints during testing.

Temporary marker posts shall be installed immediately after testing at all

junctions between tested lengths. Before any length of pipeline is subjected to test pressure, care shall be taken

to ensure that all weight, thrust and anchor blocks intended to prevent vertical and lateral displacement of pipes or specials have been properly completed. All valves shall be checked before the test to ensure that they are in working order.

Prior to filling the line with clean water for water testing, the line shall be

thoroughly inspected jointly with the S.O. to ensure that the line is cleaned from stones, dirt, debris, plastic paper or any other matter that may have entered after laying of pipework.

The water for filling and testing the pipeline shall be obtained from an

approved source. It shall be free from silt, contamination and pollution. The Contractor shall make all arrangements necessary for conveying the water to the point of filling. The test ends shall be tapped for suitable size test connection. When using high pressure pumps for water feeding, regulate the feed slowly to allow minimum or bubbles into the pipeline.

The fill and test position shall be located at the lowest point of the pipeline

profile to encourage the expulsion of air as the pipe is being filled. All air-valve positions and the end of the test section shall be vented during the filling of water to bleed out all trapped air which may affect the test.


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The Contractor shall supply all necessary apparatus including pipework, pumps, flowmeters and pressure charts/recorders and carry out all work necessary to test the pipeline. Pressure gauges are to have a dial at least 200 mm in diameter and shall have unit graduations on the gauges of not more than 0.1 bar. The pressure recorders shall have the ability to record pressures down to 0.1 bar. The gauges and recorders are to be checked against a guaranteed standard unit before use and at other times as the S.O. may direct. The flowmeter to measure the quantity of flow pumped shall be suitable for the flowrate of the pumps supplied by the Contractor. The flowmeter shall have an accuracy of not more than 2% at transition flowrate of the meter as specified in BS5728. The flowmeter shall have an integral totaliser display built-in.

The S.O. will attend all tests and all apparatus and methods shall be to his

approval. No length of pipeline shall be deemed to have passed its pressure test until the S.O. has issued a certificate to the Contractor to this effect.

Substantial completion will not be certified before the mains have been

successfully water tested. The Contractor shall take all necessary steps to locate any leakage, supply

necessary materials and make necessary repairs or remake any joints, and restore the ground at no extra cost to the Contract until, on retest, the requirements of permissible loss are complied with.

A pressure test on washout pipework shall not be required. The performance

of washout pipework shall, however, be observed during flushing of the pipelines after testing. Each scour valve in turn shall be opened fully under the normal working head in the pipeline for sufficient time to allow proper flushing of the pipeline and to check the watertightness of the washout pipework. All water used for testing purposes shall be recorded. The Contractor shall carry out any necessary remedial work to pipework as directed by the S.O.


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SECTION 2.0 – MILD STEEL PIPES AND

SPECIALS



2.0 MILD STEEL PIPES AND SPECIALS 2.1 General

All pipes, specials and fittings must be from SAJH approved sources and be to SAJH specifications (SAJH PS/MS/001).

2.2 Scope This section of the Specification covers the requirements for the manufacture

and testing of welded steel pipes together with specials complete with internal and external protection systems.

2.3 Definition The following terms shall have the meanings hereby assigned to them except

where the context clearly renders these meanings inapplicable. "Pipes" means straight pipes, whether whole or in cut lengths. "Pipe specials or specials" means tees, bends, tapers, collars, flange

adapters, blank flanges, expansion joints, mechanical joints, ring girders and similar accessories.

2.4 Standards and Codes of Practice The following Standards and Codes of Practice are referred to in this section

of the Specification. The Standards or Codes shall be the latest edition current at the time of its preparation unless otherwise specified for particular application:-

API 5L : Line pipe API 5LS : Spiral-weld line pipe API 1104 : Standard for welding pipe lines and related

facilities BS Handbook 19 : Methods for sampling and analyses of iron, steel

and other ferrous metals BS 12 : Specification for ordinary and rapid hardening

Portland cement

BS 3601 : Specification for carbon steel pipes and tubes with specified room temperature properties for pressure purposes

BS 729 : Hot dip galvanised coatings on iron and steel articles

BS 534 : Steel pipes, fittings and specials for water, gas and sewage


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BS 903 : Methods of testing vulcanised rubber

BS 1154 : Specification for natural rubber compounds (high quality)

BS 2494 : Materials for elastomeric joint rings for pipework and pipeline

BS 2569 : Sprayed metal coatings

BS 4147 : Hot applied bitumen based coatings for ferrous products

BS 4232 : Surface finish of blast-cleaned steel for painting

BS 4360:1986 : Weldable structural steels

BS 4504 : Flanges and bolting for pipes, valves and fittings Part I: Ferrous

BS 4515 : Welding of steel pipelines on land and offshore.

BS 5135 : Process of arc welding of carbon and carbon manganese steels.

BS 5292 : Jointing materials and compounds

BS 5500 : Unfired fusion welded pressure vessels

AWWA Mll : Steel pipe design and installation

2.5 Submissions The Contractor shall provide drawings, calculations and data in respect of

the following:- i) For pipes and specials : Drawings with descriptions to show the method of forming pipes and fittings

in standard lengths from steel sheets or strip. ii) For joints : Drawings for spigot and socket joints showing allowable tolerances and

arrangements to permit air testing of completed joints on Site. iii) For welding procedure : Details of plant, methods, materials, make and size of electrodes, number of

runs and current strength for each type of weld.


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iv) For internal lining: Full details of method of lining and curing including details and sieve analyses

of materials to be used and type of cement. v) For external coating: Full details of coating process to be used, including details of the bitumen and

the inner and outer wrappings or equivalent subject to the approval of the S.O.

2.6 Pipes and Specials All pipes and specials shall be provided by the Contractor and delivered to

the Site. Each item supplied shall be suitably marked to permit identification with items in the Bill of Quantities.

2.7 Steel Pipes Steel pipes shall be manufactured, except where stated otherwise hereunder,

in accordance with BS 534. Material for pipes shall be made from carbon steel plate to Grade 43A of BS 4360:1986 or better with a minimum lower yield stress of 275 N/mm2 supplied in plate or strip form as of appropriate for the method of pipe manufacture. The pipes shall be formed by the automatic submerged arc process, with either a longitudinal seam or a spiral seam at the option of the Contractor. With the method of manufacture decided upon, the relevant standard will then apply i.e. BS 534

The Contractor shall provide a ladle analysis of the steel used for the pipes

in accordance with Clause 7.1 of BS 4360:1986. Check analyses of the finished pipe shall be taken in accordance with Clause 7.2 of BS 4360:1986. In case of dispute, the methods of chemical analysis shall be in accordance with BS Handbook No. 19.


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Unless otherwise specified, thickness of the steel pipe shells and the finished internal diameters of the pipes shall be as shown in the following table :-

Outside

Diameter (O.D) (mm)

Nominal Diameter

(ND) (mm)

Minimum Nominal

Thickness (mm)

Concrete Lining

Thickness (mm)

Bitumen Enamel

Wrapping (mm)

Mass per

length (plain end)

Hydraulic Test

Pressure (Steel430)

88.9 114.3 139.7 168.3 193.7 219.1 244.5 273

323.9 355.6 406.4 457 508 559 610 660 711 762 813 864 914 1016 1219 1422 1626 1829 2032 2235

80.0 100 125 150 175 200 225 250 300 350 400 450 500 550 600 650 700 750 800 850 900 1000 1200 1400 1600 1800 2000 2200

3.2 3.6 3.6 3.6 4.0 4.0 4.0 4.0 4.0 4.5 4.5 5.0 5.0 6.3 6.3 6.3 6.3 6.3 7.1 7.1 7.1 7.1 8.0 8.8 10.0 11.0 12.5 14.2

6 6 6 6 10 10 10 10 10 13 13 13 13 13 13 19 19 19 19 19 19 19 19 25 25 25 25 25

3 3 3 3

4.5 4.5 4.5 4.5 4.5 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6

6.76 9.83 12.1 14.6 18.7 21.2 23.7 26.5 31.6 39.0 44.6 55.7 62.0 85.9 93.9 102 109 117 141 150 159 177 239 307 399 493 623 778

70 70 70 70 70 70 70 64 54 56 49 48 43 50 45 42 39 36 38 36 34 31 29 27 27 26 27 28

* The above finished minimum steel shell thickness shall not be subject to any negative tolerance for acceptance purpose.

The thickness of pipes used for branch pipework off the main pipelines or for use in forming specials shall be the greatest of the following:-

(a) The thickness necessary to provide the same outside diameter to

wall thickness ratio specified for straight pipes. (b) The thickness determined to be necessary in the design of

specials as shown on the Drawings. Unless otherwise approved by the S.O., standard length straight pipes shall

be manufactured with not more than three circumferential joints and with an effective length as shown in the table below:-


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Finished Internal

Diameter (mm)

Standard Length

(m)

450 and above

Below 450

9 6

As per SAJH PS/MS/001 The allowable tolerance on standard length pipes shall be + 150 mm. In

addition a number of straight pipes of half the standard length pipes and truly circular standard straight pipes shall be supplied. All standard and half length pipes shall have ends formed as specified below for joints capable of angular rotation. Truly circular standard straight pipes required for cutting purposes shall be truly circular throughout the length.

All pipes whether manufactured with a longitudinal or spiral seam shall be

subjected to non-destructive testing of seam welds and skelp. 2.8 Material, Workmanship and Welding Standards Material inspection before rolling shall be carried out to check against Mill

Certificates submitted for conformity with the BS 4360. This shall include determination of country of origin, manufacturer, physical inspection, checking of thickness and visual inspection of edges for lamination.

As a control on weld quality the Contractor shall be required to take and

submit radiographs for 3% of all welded length. The acceptance of these radiographs shall be in accordance with BS 534 or equivalent as directed by the S.O. Weld defects shall include cracks, lack of complete penetration, lack of complete fusion, and undercutting or reduction in pipe wall thickness adjacent to a weld exceeding 0.5 mm in depth.

Slag inclusions and gas pockets or voids considered to be minor

imperfections may be accepted if the maximum size and distributions does not exceed the limits.

Where radiographic examination reveals defects in the welds the S.O. will

either reject the length of pipe containing such defects or will permit the Contractor to carry out repairs and to submit radiographs of such repairs for clearance. Lengths of pipe containing defects in welds after repair will be liable to be rejected.

If defects in welds are found in a length of pipe or specials, the welds of the

pipes and specials immediately before and after the defective pipe or specials in the production line shall be radiographed until the S.O. is satisfied that all the welds are considered satisfactory. The cost of such radiographs of repaired welds shall be included in the Contract Rates and shall not form part of the 3% of all welded length specified in the first paragraph of this Clause.


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2.9 Pipe Ends Ends of pipes to be jointed shall generally be as follows :-

(a) Spigots and sockets for jointing in trench or above ground. (b) Plain ends for use with welded collars, mechanical couplings or

flange adaptors. The spigot and socket joints for the spherical type shall be designed to take

angular deflections of up to 5 degrees from the axial to accommodate changes of pipe gradient and/or direction at individual joints. For hemispherical type, the angular deflections shall be up to 2 degrees.

Spigot and socket joints shall be of the spherical or hemispherical sleeve

type with a minimum penetration of the formed ends. The joint design shall provide for the contact surface of the spigot end and the sleeve end to be formed to the same spherical radius which shall be more than 50% of the outside diameter of the barrel of the pipe for the spherical type and shall not be less than 50% of the outside diameter of the barrel of the pipe for the hemispherical type. The minimum penetration of the spigot into the socket shall not be less than four times the pipe thickness and this overlap shall be obtained at the maximum deflection of 5 or 2 degrees excluding pipe lining. At zero deflection the minimum overlap shall be the minimum penetration as above increased by such allowance as is necessary to ensure contact between the spigot and socket over the specified maximum amount of joint movement. The joint engagement tolerance in any position shall not exceed an average of 1.60 mm with maximum isolated gaps of 2.00 mm adjacent to the weld seams.

Pipe ends of the spherical or hemispherical type shall be formed by hydraulic

pressing using a full circle die or expanding former capable of forming ends consistently to a constant spherical contact surface throughout the pipe production run.

The internal surface of the socket and the external surface of the spigot shall

be ground smooth along the shop fusion welds for a distance of 150 mm from pipe ends measured along the pipe axis.

The external surface of the plain ended pipes shall be similarly prepared.

All sockets shall have two tapped holes spaced at 90 degrees apart on the circumference. They shall be of not less than 6 mm diameter and shall be provided with matching plugs to facilitate the air pressure testing of field welds. These tapped holes shall be located within the end 30 mm of the sockets and shall be cleared of welding runs.

Ends prepared for butt welding shall be subject to manufacturing tolerances

in accordance with Table 6.3 of Std 5L or Table 6.2 of Std 5LS.


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Plain ends for use with mechanical joints or flange adaptor joints shall be truly circular with a diameter tolerance of + 1 mm over a distance of 225 mm from the pipe ends.

2.10 Bends, Tees, Tapers, Etc. Special items such as bends, tapers, tees, etc, shall be formed from

completely lined pipes as specified by suitable insertion of rubber spacers during lining operation. The coating and lining on the straight pipes shall be cut back from the ends to be welded or cut for a sufficient distance to ensure that no material which is intended to remain part of the coating/lining is damaged or affected by the welding or cutting process.

Pipe specials shall be designed to withstand the full specified factory test

pressures. Compensation plates and gusset plates shall be in accordance with BS 5500.

Welding shall be of a standard equal to that of straight pipes and each butt

weld shall be subjected to a 100% radiographs test. Fillet welds shall be subjected to air tests where appropriate and/or magnetic particle testing.

The outside diameter of specials shall conform to the outside diameters of

the standard straight pipes. The ends of plain ended specials shall be truly circular and shall conform to the tolerances required for the fitting of mechanical couplings and flange adaptors.

2.11 Flanged Joints All flanges shall be of steel, welded to the pipe by the electric arc process or

other approved method. They shall conform in all respects with the requirements of BS 4504 unless otherwise specified. They shall be of the raised face type and shall be truly faced over their whole width. Bolt holes shall be drilled off centre lines, truly in line end to end with the longitudinal axis. All flanges shall be rated as 16 bar and confirm to table 11 of BS 4504 unless otherwise stated. All flanges shall be adequate to withstand test pressures for the fittings to which they are attached and shall be in accordance with BS 4504.

All materials required for use in the making of flanged joints including nuts,

bolts, washers and joint gaskets shall be supplied by the Contractor. Joint gaskets shall be contained within the bolt pitch circle and shall be made from 4.5 mm thick rubber to BS 1154 Class Y3 reinforced with two layers of fabric in accordance with BS 5292. Each bolt shall be supplied and installed with a nut and two washers and each bolt shall be of sufficient length to show two threads past the nut when so installed.

Test certificates for the flange material shall be supplied. The finish on flange joint surfaces shall be in accordance with Clause 4.4 of BS 4504.

Blank flanges shall be designed and supplied by the Contractor for an end loading equivalent to the rating pressure of the flange. Lifting eyes or handles and air release cocks shall be provided as necessary.


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Thrust flanges shall be designed to withstand a longitudinal force equal to the loading applied to a blank flange of equivalent diameter.

2.12 Mechanical Couplings, Flange Adaptors and Expansion Joints Mechanical couplings for jointing plain ended pipes shall be of an approved

make capable of maintaining a watertight joint over a range of axial movement between the pipe ends of at least 9.5 mm and with up to 3 degrees angular deflection between the longitudinal axis of the pipes.

Flange adaptors for jointing plain ended pipes to fittings shall be of an

approved make capable of maintaining a watertight joint over a range of axial movement of at least 4.8 mm and an angular deflection of not less than one and a half degrees. All flanges shall be drilled in accordance with BS 4504 and details derived from flange design computation based on 16 bar pressure rating by the Contractor.

Expansion joints shall be provided to conform with details as shown on the

drawing. They shall be supplied complete with all accessories. All necessary couplers, joint rings, nuts, bolts and washers, etc. required for

completing joints shall be supplied by the Contractor. All bolts, nut and washer shall be hot-dip galvanised in accordance with BS 729.

Couplings shall be supplied with or without a central register or locating

plugs as required. The central collar shall be at least 1.5 mm thicker than the equivalent standard pipe thickness.

Every coupling, flange adaptor and expansion joint shall be capable of

withstanding without leakage the pressure required for the works hydraulic test of the section of pipeline in which it will be incorporated. The pressure rating shall be clearly stamped on all couplings and adaptors. The rubber joint rings shall be Type 1 to BS 2494 having a hardness range of 45-65 degrees measured in accordance with BS 903 and tensile stress-strain properties detailed in Table 3 corresponding to the relevant hardness.

All metallic parts are to be descaled to first quality standard in BS 4232 and

protected with two coats of approved two-pack epoxy based enamel unless otherwise stated. The enamel shall be taint free, non-toxic and chlorine resistant.

All welding protrusion shall be machined finished. Mechanical couplings and

flange adaptors shall be hydraulic tested at the place of manufacture one in every five for each size of coupling and adaptor. Test certificate shall be provided by manufacturer.

Every expansion joint shall be hydraulic tested at the place of manufacture

prior to delivery.


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2.13 Pipes for Closing Lengths Pipes to be used for closing lengths shall be correctly sized over their full

length so that accurate alignment for split collar joints can be obtained. All such pipes shall be clearly marked.

2.14 Collars Collars shall be provided for jointing cut pipes or closure pieces by means of

internal and external fillet welding. Minimum lengths of collars shall be 250 mm. Collars may be provided as single split collars with temporary bolts and lugs. Collars shall have two tapped and plugged holes of not less than 6 mm diameter to permit air pressure testing of the joints after field welding, one each side of the collar clear of the welding runs and approximately 25 mm from the edge of the collar. The collar shall be 1.5 mm thicker than the equivalent standard straight pipe thickness. Collars shall make close contact around the circumferences of both pipes connected and the gap between the ends of a split collar after tightening shall not exceed 3 mm. Split collar ends shall be prepared for butt welding in the same manner as plain ends of pipes prepared for butt welding in accordance with Std 5LS. The tolerances of the collar shall be such that nowhere shall the gap between the inside surface of the collar and the outside surface of the pipe at fillet weld locations exceed the tolerances permitted for spigot and socket joints.

The overlap on each pipe shall not be less than 75 mm. Collar joints shall

not be required to take any deflection. 2.15 Retaining Rings All flanged pipe ends, flanged branches and plain ends for use with

mechanical couplings or flange adaptors shall have a 6 mm steel retaining ring welded into the bore of the pipe flush with the end of the pipe after which the ring shall be zinc phosphate coated as specified followed by two coats of bituminous paint. The radial thickness of the rings shall be similar to the thickness of the concrete lining and shall not be less than 6 mm. The ring shall be protected with two coats of approved two-pack epoxy based enamel if it is too thick to be effectively covered by the concrete lining.

2.16 Physical Testing Unless otherwise specified physical testing of the pipes shall also be in

accordance with Section 4 of Std 5L/S. 2.17 Works Hydraulic Testing All pipes shall be hydraulically tested at the place of manufacture in

accordance with BS 3601. Full test pressures shall be maintained for at least 3 minutes during testing at the factory and automatic pressure recorders must be installed on hydraulic testing machines.


15


Any pipe which fails to withstand the hydraulic test pressure or which exhibits signs of porosity shall be deemed not to comply with this Specification and shall be rejected unless otherwise decided.

2.18 Ring Girders Ring girders shall be provided to conform with details shown on the

Drawings. They shall be supplied complete with all accessories. Metallic parts are to be descaled to first quality standard in BS 7079 and painted with two pack polyamide cured epoxy zinc phosphate primer with 75 microns minimum dry film thickness.

2.19 Protection All pipes shall be protected both internally and externally against corrosion.

The pipes shall be protected externally with a double reinforced bitumen enamel wrapping followed by internal protection with spun concrete lining. Both types of protection shall be applied under factory conditions but not necessarily at the place of manufacture of the pipes.

Internal and external protection at joints shall be completed on Site after

acceptance of joint weld tests. 2.20 Cleaning and Priming Where bitumen wrapping is to be applied at the place of pipe manufacture,

cleaning and priming shall immediately follow hydraulic testing. Where bitumen wrapping is to be applied at another location, then the pipes shall be coated with a suitable corrosion inhibitor before despatch from their place of manufacture.

Immediately prior to priming, all pipes shall be thoroughly descaled by shot

blasting internally and externally to BS 4232 second quality. If the spun concrete lining is to be applied at the place of pipe manufacture,

internal priming of the pipe barrel may be omitted. Otherwise pipes shall be primed both internally and externally.

The above priming shall stop short of the ends of pipes intended for field

welding. The ends of such pipes shall be coated with an approved priming paint and/or rust inhibitor both internally and externally. This shall be suitable for providing a temporary protection from rusting prior to field welding those areas of pipe not given the full factory applied permanent protection and shall not affect the weldability of the metal.

2.21 External Coating The pipes shall be coated with bitumen generally in accordance with Clauses

29 of BS 534 except that the protection shall have a minimum thickness of 4.8 mm for pipes over 324 mm od. The bitumen shall be Type 2 of BS 4147


16


and there shall be not less than 2 mm of bitumen between the inner and outer wraps, and between the pipe and the inner wrap.

The coating shall be stopped short as shown on the Drawing for ends of all spigot and socket pipes, and 250 mm from the ends of all plain ended pipes

for use with mechanical couplings or flange adaptors. The edge of the wrapping shall be chamfered at 25 degrees.

2.22 Wrapping The wrapping materials shall be spirally wound onto the pipes and specials

simultaneously with the bitumen coating. Each wrap shall be from 150-225 mm wide and the edges shall overlap by 12-25 mm. Care shall be taken to ensure that the inner wrap does not come into contact with the pipe metal or with the outer wrap.

The inner wrap shall be a glass fibre resin-bonded tissue reinforced in the

longitudinal direction with parallel glass threads spaced 10 mm apart. The nominal thickness shall be 0.5 mm and the minimum weight shall 0.046 kg/m2. The outer wrap shall be of glass fibre resin-bonded tissue reinforced in the longitudinal direction with parallel glass threads spaced 10- 25 mm apart. It shall be impregnated with a material fully compatible with the bitumen coating to give a finished thickness of 0.75 mm.

2.23 Inspection of External Pipe Coating All coated pipes and specials shall be rigidly inspected for defects. Thickness

shall be determined by a pit gauge, continuity with a holiday detector and coating quality by cutting out 75 mm square samples at the rate of one sample per 5 lengths of pipe manufactured.

The whole coated surface area of all pipes and specials shall be tested for

pinholes or other invisible defects in the coating using an approved holiday detector at a potential of 14,000 volts. Any lengths on which the coating is, in the opinion of the S.O. poorly applied shall be cleaned to bare metal and re-coated. Minor defects may be repaired by touching up. All repairs shall be checked for thickness and continuity.

2.24 Painting Unwrapped Pipes and Specials All unwrapped pipes and specials shall be given two layers of primer coat of

Red Lead Oxide and two layer of final coat of light green zinc chromate. The internal lining will be similar to the requirement of wrapped pipes.

2.25 Spun Concrete Lining at Factory

All pipes and specials shall be lined with concrete. Cement for lining shall be ordinary Portland cement to BS 12. Aggregate shall be well-graded clean fine


17


aggregate and the maximum particle size shall not exceed 8 mm or one third the thickness of the lining, whichever is the lesser. All materials used in concrete for lining shall comply with the requirements for concrete.

The final aggregate grading and concrete mix proportions shall be such that a hard, durable and dense concrete lining is obtained that satisfies the tests laid down in Clause 33 of BS 534. Unless otherwise approved, the minimum cement content shall be 330 kg/m3 and the water cement ratio of the mix loaded into the pipe shall not exceed 0.42. Tests shall be carried out during the lining of pipes to demonstrate that the concrete lining has a strength equal to or greater than the minimum figures stated in Clause 33.5 of BS 534. The frequency of these tests shall be at least once every 250 m length of pipe lined or during each working shift, whichever is the greater. The testing of concrete cubes shall be conducted at the factory of manufacture and certificate for testing shall be provided. All straight pipes shall be concrete lined by the use of a lining machine designed and built for the purpose of rotating the pipe and centrifugally applying the lining at sufficient speeds to meet the requirements set out below. The support or holding device for the pipe shall be such as to avoid damage to the pipe coating during the spinning operation. If the pipe is rotated by direct contact drive from the machine it shall be supported over at least 90 degrees of its circumference and driven by non-metallic surfaced belts of sufficient width to avoid coating damage. The speed of rotation of the pipe during the lining compaction stage shall be such as to provide a radial acceleration of at least 250 m/s2. The rotational drive shall be capable of close control and provide smooth acceleration and deceleration when working up to and down from the compaction spinning stage. Immediately before lining commences, the pipe bore shall be cleaned of all loose scale, rust, oil, grease or any other foreign matter likely to contaminate or harm the concrete. Areas where an approved priming coat has bonded to the pipe such that wire brushing does not cause areas to flake off will be acceptable as a base for applying the lining. The entire quantity of concrete required for the lining shall be applied without interruption, and spinning shall continue until the specified thickness is evenly distributed over the inside of the pipe, all surplus water has been removed and the greatest possible density of concrete has been obtained. Tolerance on the thickness of lining shall be as follows :- (i) +3 mm to -2 mm for 25mm and above (ii) +2 mm to -1 mm for 19 mm and below Temporary or semi-permanent end restraints shall be fixed to the pipe ends on completion of lining and before removal of the pipe from the lining machine. The pipe shall not be rotated about its longitudinal axis after the fixing of the restraints when being handled and transported to the storage yard and subsequently to the Site. Pipe specials shall be concrete lined at the factory in such a manner that the lining shall be of the specified thickness and comparable in density and smoothness to the spun lining in straight pipes and generally applied in


18


accordance with Clause 33.2 of BS 534. During the lining process, all rebound material, dribbles, etc. shall be removed so that the lining is applied in a homogeneous mass to a clean surface.

Inspection of the lining shall be carried out at any time prior to and after installation of the pipes. Any pipe with lining that is broken, defective or otherwise not in accordance with the Specification may be rejected. Remedial lining operations may be carried out by a method that has been approved in writing in advance by the S.O.. The standard of the remedial lining shall satisfy the requirements of this Specification. Surface crazing of the lining will be acceptable unless cracks are severe enough that they can be penetrated to a depth of 2 mm by a 250 microns feeler gauge at 10 points or more over a length of 300 mm when measured with the lining in a saturated condition. These cracks shall be cut back to full depth and sealed with an approval epoxy resin filler. Linings applied to pipes shall be cured in such a manner as will enable concrete to obtain and subsequently retain optimum strength, density and durability. Linings shall be kept moist by continuous water spraying for a period of at least 3 days. They shall then be protected from sunlight and kept damp by spraying with water or other means approved by the S.O. for a further period of 7 days. Pipes shall not be removed from the factory until at least 14 days have elapsed from the date of lining.

2.26 Internal Protection at Pipe Ends Concrete shall be omitted at the following locations :- a) Spigot & Socket Ends The lining shall terminate as shown on the Drawing. The edge of the

lining shall be angled back at 3mm to the pipe axis in order to provide a positive key for in-situ joint protection.

b) Plain Ends For butt straps or collar joints, the lining shall terminate 90mm back

from the pipe end. The edge of the lining shall be angled back at 3mm.

For mechanical coupling and flange adaptor joints, the lining shall be

brought right against the retaining rings. 2.27 Pipework for Laying above Ground Uncoated steel pipes and specials required for installation above ground

shall be cleaned to BS 4232 second quality and protected with two layers of primer coat of Red Lead Oxide and two layer of final coat of approved zinc chromate primer.


19


2.28 End Protection The concrete lining and the external coating of pipes and specials to be

jointed by welding shall be omitted for a sufficient distance from the ends to prevent damage to the protection during site welding.

The unlined surfaces shall be protected with a suitably approved ensis oil or

similar material during manufacture so that extensive cleaning of the surface is not required before and after jointing on site.

2.29 Examination of Steel Pipes Where MS pipe ends to be jointed by welding are coated with ensis oil at the

place of manufacture the ends shall be thoroughly cleaned with the ensis oil removed.

The ends of MS pipes and specials shall be cleaned by power brushed to a

minimum of 75mm from the pipe end both internally and externally. 2.30 Low Friction Coating Where necessary, the external surfaces of the pipe ends for use with

mechanical couplings and flange adaptors shall be given, after blast cleaning to BS 4232 first quality, an approved system of low friction vinyl-based protective coating. The coating shall be applied in accordance with the manufacturer's instructions. Where zinc or bituminous coatings adjoin the low friction coating, they shall overlap the low friction coating by 25 mm. The length of pipe barrel to be so protected by the low friction coating shall be 300 mm unless directed otherwise.

After curing but before removal from the factory the coating shall be wrapped

with tape suitable for protecting the coating from damage in transit to and on the Site. The tape shall be removed immediately prior to installation of the pipe or specials so coated.

A coating, which conforms to the above requirements, is "Amercoat 23"

system manufactured by Ameron, Protective Coatings Division, Brea, California 92621.

2.31 Handling Coated pipes shall be lifted and moved only by wide non-abrasive slings or

by other means acceptable to the S.O. Wire ropes, chains and hooks shall not be permitted to come in contact with the coating. No pipe shall be moved by rolling.

Coated pipes shall be stacked in one layer only and in such a manner that

the coating is not damaged. Unless under exceptional situation with adequate provision for pipe protection and handling, stacking in two layers may be considered by the S.O. Adequate packing between pipes for this purpose must be supplied by the Contractor. Coated pipes must be kept clear of the ground and rested on padded sleepers or supports.


20


The pipes shall be so handled, stored and transported as to prevent undue distortion and shall not be moved in any manner involving rotation of the pipe about the longitudinal pipe axis.

The pipes shall be lifted by means of two reinforced canvas slings at least

300 mm wide suspended from a lifting beam so that the slings are positioned at a distance of one-fifth of the pipe length from each end of the pipe. On no account shall the pipes and specials be dropped or let fall onto the ground and under no circumstances shall the pipes and specials be lifted by means of hooks to the ends of pipes and specials.

The Contractor shall provide suitable timber end struts and sufficient

intermediate struts to strengthen the pipes to the S.O.'s approval to prevent distortion during handling and delivery. Such struts shall be left in position when thin wall pipes of 1400 mm and above are delivered to the storage areas.

Attention is drawn to the Contractor that thin wall pipes, defined as pipes

with a diameter/plate thickness ratio greater than 125, shall be so handled, stored and transported as to prevent distortion or damage to the pipes and shall not be moved in any manner involving rotation of the pipe about the longitudinal pipe axis. Thin wall pipes during delivery and when in transit around the Site shall be supported on three rubber covered saddles shaped to give at least 90° circumferential support and shall be firmly held in position at each saddles by straps tightened of turnbuckles in such a manner that the external coating is not damaged. One saddles shall be in the centre of the pipe length and the other two shall each be positioned at a distance one-fifth of the pipe length each end of the pipe.

Thin wall pipes in temporary storage or strung out along the pipeline

reservoir routes shall be supported on hessian bags filled with the sawdust straw or similar and shaped so as to give continuos support under at least 40-50° of the circumference. The positions of supports shall be the same as that for pipes during transit. The underside of the pipes shall be kept clear of the ground by at least 300 mm.

The Contractor shall be deemed to have allowed the cost of providing the

above necessary measures in the Contract Rates for hauling and laying. Any damage to or loss of materials shall be made good, or the damaged or lost materials inforced, by the Contractor at his own expense and if approved in by the S.O. damaged materials shall be returned to the manufacturer for repair as directed by the S.O.

2.32 Repair of Lining and Sheathing of MS pipes

Only specially competent and skilled men shall be employed to carry out repair work to damaged linings and sheathing.

Small cracks and flaws in the internal mortar lining of steel pipes and specials

may, with the prior approval of the S.O. and if they are accessible, be repaired on Site. Such cracks may be repaired by cutting out a 9 mm x 9 mm dovetailed key and making good with a semi- dry mortar (proportion 1 part cement to 2 parts coarse sand) well tamped into the groove, and cured


21


by keeping it damp for 7 days. Alternatively, small cracks may be caulked with an epoxy resin filler.

The external sheathing of steel pipes and specials shall be made good

wherever the steel has been exposed or the thickness of the coating seriously reduced by damage, or where the coating does not adhere tightly to the steel.

Where the steel has been exposed all rust and dirt shall be removed

carefully by wire brushing or otherwise, and when perfectly clean and dry, a coat of approved special quick drying primer applied before re-fettling. Small stones, which may have become embedded in the sheathing, shall be picked out and the coating refettled by heating locally with a blow lamp and smoothing over with a fettling knife. Additional external jointing material shall be added wherever necessary.

All defects to linings and sheathings shall be made good to the entire satisfaction of the S.O. Where in his opinion the damage is such that satisfactory repairs on Site will not be practicable, e.g. when damage or cracking is extensive and/or inaccessible, the pipes or specials in question shall be either returned to the factory for repairing properly or replaced completely. The Contractor shall be responsible in either case for all costs involved in this respect and for any delays to construction work thereby caused. The compound used for repairing sheathings shall be compatible with the sheathing material and shall be approved by the S.O.

2.33 Laying MS Pipe No pipes shall be rolled into place for lowering into the trench. If a crane is

used for handling the pipes into the trench, the pipes shall be slung with slings passed around the outside as specified in Clause 2.31. A recess shall be formed in the trench foundation beneath to permit each sling to be withdrawn without damage to the pipe coating or sheathing. All struts at the ends of the pipes and pipe specials shall not be removed until they are ready for engagement.

Before any pipe or special is lowered into the trench, it shall be cleaned and

re-examined for cracks and flaws whilst hanging in the sling. The trench bottom shall be free from all rock, boulders, stones or hard particles, which may cause damage to the sheathing of MS pipes. The trench shall be bedded as shown on the drawings. If the pipes are undamaged and the trench bottom bedded properly the pipes shall be placed in position ready for jointing. Care should be taken not to drop the pipes particularly at fabricated fitting junctures.

Except for pipework to be embedded in concrete, all pipes and specials shall

be placed on a solid and even foundation for their full length. Pipes and specials shall be placed in position singly and the order of laying pipes shall be subject to the approval of the S.O.

Joint holes for shall be formed in the excavation as necessary for the

convenient and proper making of the welded joints, and each pipe or specials shall be individually set for line and level using boning rods.


22


Pipes and specials to be embedded in concrete shall be held firmly in position and protected from damage while the concrete is being placed. Should any pipe become either partially or wholly clogged before final acceptance of the work, it shall be cleaned out or replaced by the Contractor at his own expense.

After laying, the interior of pipes or specials shall be carefully cleaned again

to remove any debris, dirt, stones or other matter that may have entered during laying.

Except when work is actually proceeding, all open ends of pipes and

specials in the trench shall be kept closed by means of a fine wire gauge wooden stoppers or other approved means, to prevent the entry of dirt, stones and the like, but such stopper shall allow the entry of water.

2.34 Welding MS Pipe All electric arc welding equipment shall be to the approval of the S.O.. The Contractor shall submit details of the welding procedure which he

proposes to adopt for the S.O.'s approval. Details shall include: - (i) Make, type and gauge of electrodes (ii) Size, shape and number of runs in welded joint (iii) Direction of welding

(iv) Current strength (v) Welder competency certificate

The Contractor shall make test specimens on pipes of the same size and

thicknesses as the pipelines to be welded. These pipes shall be supplied by the Contractor. The joints shall be tested in the presence of the S.O. for each procedure proposed in accordance with the requirements of BS 4515.

Only procedures approved in writing by the S.O. shall be adopted in the

welding of the pipelines, and change from one procedure to another will not be permitted without submitting the new procedure for re-testing.

2.35 Making Welded MS Pipe Joints Where the steel pipes are to be jointed by welding it shall be by means of an

internal and an external circumferential electric arc weld at each joint. Before placing the pipes together the portion of the sockets and spigots to be welded shall be cleaned to a bright metallic finish, the spigot end shall then be placed in the socket and forced inside so that the spherical surfaces are in contact and that the gap between the pipes at the end of the spigot is nowhere greater than 1.5 mm. For longitudinally welded pipes, the longitudinal welds on adjacent pipes shall be at least 15o out of line. Details of the socket and spigot welded joint are shown on the Drawings.

Where pipes are to be jointed by a steel split collar, the pipe ends and the

collar shall be cleaned to a bright metallic finish. The collar shall then be placed on the ends of the pipes so that the space between the pipe ends shall be about 25 mm from the centre line of the collar. The collar shall be clamped


23


tightly onto the pipes using the lugs and welded longitudinally. After completion of the internal and external circumferential welds, the lugs shall be removed and the longitudinal weld completed.

The weld shall be of the convex full fillet type for lap welded joints made

manually by the metal arc process using approved types of electrodes. Each time the arc is started it shall be manipulated to obtain complete fusion of the weld metal with the pipe metal and any previously deposited weld metal. Before welding over any previously deposited weld metal all slag shall be completely removed and the weld metal and the adjacent pipe metal shall be cleaned by wire brushing.

All welds shall be subject to inspection by the S.O. and shall comply with the

requirements of BS 5135 for freedom from undercutting, fusion penetration and soundness.

Welded joints for large diameter pipes of 1000 mm dia and above shall be

radiographed at random as directed by the S.O. At least 2 strips each for internal and external welds shall be sampled for quality check for a slip joint. The Contractor shall make all the necessary arrangement apparatus and equipment and a specialist to carry out the test. The analytical report in duplicate shall be submitted to the S.O. three days after the test. If the weld does not meet the requirements of the Specification, the welds will have to be gouged out and made good. The repaired welds shall be radiographed again at no extra cost to the client.

2.36 Air Testing of Welded MS Pipe Joints For MS pipes of finished internal diameter larger than 628mm, after each

joint has been welded it shall be air tested in the presence of the S.O. The annular space between the two welds shall be air tested to a pressure of

1.7 MPa. While this pressure is maintained for a minimum period of ten minutes, the welds shall be examined carefully for leakage. Any defective welding shall be treated as directed by the S.O.. The tap holes shall be then sealed off with welding after each joint has been satisfactorily tested. The Contractor shall provide all necessary gauges, pumps, etc, for the air testing.

2.37 Completion of Sheathing at Welded MS Pipe Joints After the S.O. has advised the Contractor in writing that a welded joint has

passed the air test the external sheathing shall be completed to ensure continuity of protection along the pipeline.

Bare metal shall be thoroughly cleaned to a bright metallic finish and it shall

be immediately coated with a primer solution. The primer shall be applied cold by brush.

As soon as the primer has set the sheathing shall be completed by running

hot bitumen into a metal mould placed over the joint and overlapping the sheathing by 75 mm on either side of the joint. The bitumen shall be Type 2 of BS 4147.


24


Priming and sheathing material for the purpose shall be provided by the Contractor including the supply of all the necessary mould boxes and funnels required to form the protective mould and whiting for use in lining the mould boxes prior to each pour. The Contractor shall also supply all necessary boilers to heat the bitumen to the application temperature recommended by the manufacturer.

The use of method other than the above shall subject to the approval of the

S.O.. 2.38 Completion of Internal Lining at Welded MS Pipe Joints For MS pipe larger than 628mm finished internal diameter, on completion of

the external sheathing, the steel exposed by the gap in the internal lining, together with the adjacent lining shall be thoroughly cleaned and wire brushed. The adjacent lining shall be wetted with thick cement slurry but no accumulations of water in the gap shall be allowed. The internal lining shall then be made from one volume of cement to two volumes of fine aggregate to ensure a smooth continuous lining throughout the pipeline. Where necessary wire mesh may be introduced for ease of completing thick concrete lining particularly those of spherical type joints.

2.39 Testing MS Pipeline 2.39.1 Test Pressure The test pressure to be applied shall be 15 bar at the lowest point. 2.39.2 Leakage Testing In testing, the main shall be filled with clean water and properly vented to

remove trapped air. After a period of 24 hours, the pressure shall be raised by pumping to the specified test pressure. Pumping shall then cease at 10 bar and after a period of 24 hours, pumping shall be resumed and the quantity required to be pumped, in order to restore the test pressure, divided by the time, shall be the measure of the rate of loss.

The length of main under test shall be deemed to have passed the test if the

leakage does not exceed 0.1 litre per mm of internal diameter per 24 hour per kilometre of pipeline per 30m of water pressure.

2.40 Protection in Transit All pipes and specials shall be protected prior to despatch from the

manufacturer's works. All flanges shall have wooden discs bolted on. All other ends of pipes and fittings shall be protected against impact damage and entry of foreign matter. The protection shall take into account the end use intended for the pipes and whether or not the final protection has been completed.


25


Pipes and specials shall be wrapped or cushioned so that no load is taken directly on the external coating.

2.41 Notice of Deliveries The Contractor shall send to the S.O. advance notices and obtain the S.O.'s

approval of all consignments. Every consignment shall be accompanied by a detailed delivery note with the item number of each pipe or specials itemised in the Bill of Quantities.

2.42 Pipe Dumps and Storage Yards The pipes reserve wherever available may be used as pipe dumps or storage

reserves for pipe and specials as shown on the Drawings. Where no storage dumps are available the Contractor shall have to make his own arrangement to store the pipes and fittings.

The Contractor shall prepare the areas shown on the Drawing allocated as

the storage yards at which the pipes and fittings shall be delivered. The areas shall be clear or vegetation and leveled off and the Contractor shall construct an unmetalled access track including bridges and over water courses from the main metalled road to the storage yards.

The Contractor shall provide at no extra cost to the Employer timber pieces

to keep the stored pipes clear of the ground. The Contractor shall maintain the storage yards in a condition satisfactory to the S.O. till the expiry of the Contract.

2.43 Inspection All pipes and specials to be supplied under the Contract shall be inspected

by the S.O. or an Inspector appointed by the Employer at the Contractor’s premises or at the places of manufacture if manufactured at other premises.

The Contractor shall provide such office facilities, assistance, labour,

materials, electricity supply, fuel, stores, apparatus and instruments including X-ray or gama ray equipment, ultrasonic thickness indicators and high voltage holiday detectors as may be necessary to allow a thorough and extensive inspection to be carried out.

The S.O. or the Inspector shall be entitled at all times during manufacture to

inspect, examine and test on the Contractor’s premises or at the places of manufacture if manufactured at other premises, the materials and workmanship of the pipes and specials. Such inspection, examination or testing including the inspection by the S.O. or Inspector shall not relieve the Contractor from any of his obligations under the Contract.


26


2.44 Marking of Pipes and Specials All pipes and specials supplied shall have at least the following information:-

(i) Outside diameter (in mm) (ii) The weight in Kilogram (iii) Length of the pipe (in M) (iv) ‘SAJH’ lettering (v) Manufacturer’s distinguishing mark and date of manufacture (vi) Pipe series / Batch Number

The diameter and its consecutive number of standard length pipes shall be

repeated on the lining just inside on both ends of the pipes. The item number and diameter of branch in the case of tees and the angle in

degrees in case of bends shall similarly be repeated on the lining. 2.45 Measurement of Steel Pipes and Specials The quantities set out in the Bill of Quantities are provisional only and they

are not to be taken as the actual, limiting and correct quantities of the pipes and specials to be supplied by the Contractor in fulfilment of his obligations under the Contract. For the purpose of this clause, spigot and socket ended pipes shall be measured and paid in effective length. The effective length shall mean the net length of the pipe as laid, i.e. after deduction of the length of overlap at any spigot and socket joint to be made with the pipe. All pipes and specials shall only be measured for payment after they have been laid and incorporated into the Works. Any excess pipes and specials supplied to the site shall not be measured for payment.

The cost of all works, testing and all other requirements of the Specification

including lining, coating, wrapping, etc, involved in the manufacture and delivery of the steel pipes shall be deemed to be included in the Contract Rates.


27

SECTION 3.0 – DUCTILE IRON PIPES AND

FITTINGS




28

3.0 DUCTILE IRON PIPES AND FITTINGS 3.1 General

All pipes, specials and fittings must be from SAJH approved sources and be to SAJH specifications (SAJH PS/DI/001).

3.2 Compliance With Standards

Subject to the specified requirements of this Section, the ductile iron pipes and fittings to be supplied under this Contract shall conform with the requirements of BS EN 545:2002.

3.3 Process of Manufacture

The manufacturing method for ductile iron pipes and fittings shall comply with BS EN 545:2002.

Pipes shall be cast centrifugally in metal or sand mould. Fittings and

accessories shall also be cast in metal or sand mould. Pipes, fittings and accessories may be subjected, if necessary, to suitable heat treatment in order to given them the required mechanical characteristics. The metal used shall be such that the pipes and fittings are of ductile iron with minimum strength of 420 N/sq.mm and 0.2% proof stress of 300 N/sq.mm.

3.4 Thickness and Diameters

The diameters and shell thickness of standard pipes shall be as shown in Table 3.1.

Where fittings are required to dimensions other than those specified in BS EN

545:2002, the requirements shall be stated in the Bills of Quantities and the dimensions shall be as given in the Drawings.

3.5 Length of Straight Pipes

The effective lengths of all straights pipes shall be as defined in BS EN 545:2002 and shall be 6 metres.


Table 3.1 - Thickness and Diameter of Standard Pipes

Pipe Diameter (mm)

Pipe Shell Thickness (mm)

Pipes with Flexible Joint and

Welded-on Flanges

Pipes With Cast-on Flanges

Nominal Diameter

Outside Diameter

Class 40 Class K9

Class K12

100 150

200 250 300

350 400 450

500 600 700 800

118 170

222 274 326

378 429 480

532 635 738 842

4.8 5.0

5.4 5.8 6.2

7.0 7.8 - - - - -

6.0 6.0

6.3 6.8 7.2

7.7 8.1 8.6

9.0 9.9 10.8 11.7

7.2 7.8

8.4 9.0 9.6

10.2 10.8 11.4

12.0 13.2 14.4 15.6

3.6 Tolerance On Dimensions

The tolerance on wall thickness, length, diameter and standard mass of

pipes and fittings shall be in accordance with BS EN 545:2002.

3.7 External Zinc Coating

3.7.1 General

All centrifugally cast pipes shall be given an external coating of metallic zinc with a zinc content of at least 99.9% by mass.

3.7.2 Zinc Coating

The pipe surface shall be dry, free from rust and non-adhering particles or

any oil or grease. The zinc is normally applied on the pipe with oxide skin out, at the manufacturer's option, it may be applied on a blast cleaned pipe surface.


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3.7.3 Coating Characteristics (a) Appearance The zinc coating shall cover the external surface of the pipe and the mass

of coating shall comply with 3.7.3 (b). The coating shall adhere to the pipe surface and shall not display bare patches.

A spiralled appearance is permissible provided the uniformity of the

coating complies with 3.7.3 (c). Pipes having `damaged' areas of coating of up to a maximum of 5

sq.cm/sq.m of pipe surface shall not need repair, provided that minor dimension of the damaged area does not exceed 5 mm, where damage is defined as the removal of the zinc coating. Greater areas of damage shall be repaired in accordance with 3.7.5.

At the manufacturer's option the socket face and spigot joint area may

not be coated with metallic zinc. Where the spigot joint area is not coated with metallic zinc, a coating of

zinc rich paint shall be applied to the spigot joint area in accordance with 3.7.5 (b).

(b) Zinc Coating Mass The mean mass per unit area of sprayed metallic zinc, as measured in

accordance with 3.7.4 (b), shall not be less than 130 g/sq.m. (c) Uniformity of Coating

The uniformity of coating shall be such that the mass of zinc coating of any 25mm x 25mm area shall not be less than 100 g/sq.m.

3.7.4 Verification Process (a) Visual Inspection

The manufacturer shall visually inspect every pipe for quality and uniformity of zinc coating.

(b) Determination of Mean Zinc Coating Mass The manufacturer shall carry out measurements to ensure the mean

mass per unit area zinc coatings complies with 3.7.3 (b). The determination of the mean zinc coating mass applied to pipes (see 3.8.1) shall be carried out in accordance with appendix G of BS EN 545:2002.

3.7.5 Repairs

The manufacturer shall carry out repairs to damaged areas of coating, see 3.7.3(a), or uncoated areas, e.g. the area left uncoated as result of applying


30


the token in accordance with Appendix G of BS EN 545:2002, by use either L:-

(a) Metallic zinc spray complying with the requirements of 3.7.3(b) or

(b) Zinc rich paint containing more than 90% zinc by mass in the dried film; the mean mass per unit area of this plant shall not be less than 150 g/sq.m and the mass of paint on any 25mm x 25mm area shall be not less than 110 g/sq.m.

3.7.6 Finishing Layer

After zinc coating, the pipe shall be coated with a finishing layer as specified

in Clause 3.8.

3.8 External Coating of Pipes and Fittings

Unless otherwise specified, all pipes and fittings shall be coated externally with either;

(a) Coat-tar epoxy (epoxy content approximately 12 percent and the

minimum dry thickness of the coating shall be 80 microns); or (b) Standard coating materials as specified in BS 4147:1980 type I; or (c) Standard coating materials as specified in BS 3416:1976 type II Coating may be applied by dipping, brush, spray or roller.

3.9 Internal Lining of Pipes and Fittings

The internal surfaces of pipes and fittings except blank flanges, sockets and

bellmouths shall be lined with cement mortar in accordance to BS EN 545:2002. The cement shall be ordinary Portland Cement to MS 522.1977 if pipes are locally manufactured or to BS 12:1978 if imported. The cement mortar mix shall be one part by mass of cement to 2.5 parts by mass of sand. The lining thickness shall be as shown in Table 3.2.


31


Table 3.2 - Standard Lining Thickness

ThNominal

Diameter (DN)

erna

Standard Lining Thickness (mm)

Nominal Limit Deviation Maximum crack width and radial

displacement

40 to 300 350 to 600 700 to 1200 1400 to 2000

4.0 5.0 6.0 9.0

-1.5 -2

-2.5 -3

0.4 0.5 0.6 0.8

e int

l The internal cement mortar lining of straight pipes shall be applied centrifugally in an approved plant and shall adhere firmly to the internal surface the pipe as specified in BS EN 545:2002. The surface of the lining shall be substantially smooth but the fine crazing associated with cement rich surface shall be permitted. Isolated shrinkage cracks shall be acceptable provided their width does not exceed 0.8 mm. The surface shall be substantially free from laitance and any sand segregation present shall be minimal. Damaged linings shall be made good by means and materials approved by the S.O.

3.10 Flexible Joints

Flexible joints either of the ‘push-on type’ or of the `mechanical type' shall be in accordance with the manufacturer's standard dimensions and tolerance.

Unless otherwise specified, pipes of DN 80 to DN 1600 inclusive and fittings

of DN 80 to DN 600 inclusive shall be supplied with `push-on' type joints. Pipes and fittings of other diameters shall be supplied with `mechanical' type joints. The gasket for the joint shall be in accordance with BS EN 545:2002 and BS 2494.

Flexible joints shall be supplied complete with bolts, nuts, washers, glands,

rubber gaskets and other accessories necessary for making water-tight flexible connection between spigot and socket ended pipes and fittings.

3.11 Flanged Joints

Standard flanges shall be drilled in accordance with BS EN 545:2002 and dimensionally compatible with the corresponding flanges that are in accordance with BS 4504:1989.

The pressure ratings of the flanges shall be PN 16 or PN 25 as specified in

the Bills of Quantities.


32

Each set of flange joints shall be supplied complete with nuts, bolts, washers and joint gaskets. Joint gaskets shall be in accordance with BS 4865 : Part I.


Bolts and nuts shall be mild steel, hexagonal and shall be in accordance with BS 916.

3.12 Factory Hydrostatic Test

All pipes and fittings shall be subjected to hydraulic pressure test before being lined or coated. The pipes and fittings shall withstand the factory hydrostatic test pressure as indicated in Table 3.3 without showing signs of leakage, sweating of other failure of any kind.

Table 3.3 - Factory Hydrostatic Test Pressures

Nominal Size DN

Factory Hydrostatic Test Pressures

Pipes with Flexible Joints

Pipes with Welded-On Flanges

PN 16 Flanges

PN 25 Flanges

Factory hydrostatic leak-tightness test

pressures for pipes and fittings with cast-on

flanges

80 to 300 350 to 600 700 to 800 900 to 1200 1400 to 1600

bar (gauge)

50 40 32 32 25

bar (gauge)

25 25 25 25 25

bar (gauge)

32 32 32 25 25

bar (gauge)

25 16 10 10 2*

* Additionally tested with air at a pressure of 1 bar


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3.13 Connection to Pipes of Different Type

Where different types of pipe-work material are to be jointed together, special fittings, stepped collars, stepped couplings or changed spigots are to be used. Pipes can also be jointed by flanges, when drilling dimensions is identical. The strength, class and design of all such fittings, collars and couplings shall be in accordance with provisions of this specification for pipes and fittings.

3.14 Cutting of Pipes

Pipes which are to be cut to enable fittings to be accurately positioned or to form closing pieces in any portion of the pipeline, to terminate in manholes or other parts of the work shall be cut neatly by skilled workers using pipe cutters appropriate for the type and diameter of the pipe.

The cut ends of pipes shall be smoothed and bevelled to ensure proper

positioning at the joint without damage to the jointing rings.

After cutting, damage to external coating shall be repaired by applying the original coating material by brush. Damage to internal lining shall be repaired by touching up with cement mortar of the same composition as the original lining.

3.15 Packing

Loose parts such as couplings, flanges, bolts and nuts, rubber rings and gaskets shall be packed in weatherproof crates with the identification of SAJH and content labelled.

3.16 Polyethylene Sheathing

Where sheathing of the pipeline is required due to corrosive soil, polyethylene

sheath of 200 microns thick with a tolerance of ±25 microns shall be supplied as specified in the Bills of Quantities. The sheath shall be seamless longitudinally, free from pinholes and tears and no regenerated material shall be used in the process of manufacture. Each length of sheath shall be at least 1.0 metre longer than the corresponding pipe and supplied complete with adhesive tape.

The polyethylene sheath shall be placed over the pipe starting from the spigot end. Care shall be taken to ensure that the sleeve is rolled towards the socket end without causing tear to the sheath. At joint and fittings, sufficient slack in the sheath shall be provided to prevent damage during backfilling. To prevent ingress of water and dirt between the pipe and sheath, the sheath shall be secured with adhesive tapes at folds, open ends and other parts of the pipe as required.


34


3.17 Handling

Pipes and specials shall be lifted and moved only by wide non-abrasive slings or by other means acceptable to the Engineer. Wire ropes, chain and hooks shall not be permitted to come in contact with external coatings or internal linings.

3.18 Laying DI Pipes

No pipes shall be rolled into place for lowering into the trench. If a crane is

used for handling the pipes into the trench, the pipes shall be slung with slings passed around the outside as specified in Clause 3.15. A recess shall be formed in the trench foundation beneath to permit each sling to be withdrawn without damage to the pipe coating or sheathing. All struts at the ends of the pipes and pipe specials shall not be removed until they are ready for engagement.

Before any pipe or special is lowered into the trench, it shall be cleaned and

re-examined for cracks and flaws whilst hanging in the sling. The trench bottom shall be free from all rock, boulders, stones or hard particles, which may cause damage to the sheathing of DI pipes. The trench shall be bedded as shown on the drawings. If the pipes are undamaged and the trench bottom bedded properly the pipes shall be placed in position ready for jointing. Care should be taken not to drop the pipes particularly at fabricated fitting junctures.

Except for pipework to be embedded in concrete, all pipes and specials shall

be placed on a solid and even foundation for their full length. Pipes and specials shall be placed in position singly and the order of laying pipes shall be subject to the approval of the S.O.

Joint holes for shall be formed in the excavation as necessary for the

convenient and proper making of the welded joints, and each pipe or specials shall be individually set for line and level using boning rods.

Pipes and specials to be embedded in concrete shall be held firmly in

position and protected from damage while the concrete is being placed. Should any pipe become either partially or wholly clogged before final acceptance of the work, it shall be cleaned out or replaced by the Contractor at his own expense.

After laying, the interior of pipes or specials shall be carefully cleaned again

to remove any debris, dirt, stones or other matter that may have entered during laying.

Except when work is actually proceeding, all open ends of pipes and

specials in the trench shall be kept closed by means of a fine wire gauge wooden stoppers or other approved means, to prevent the entry of dirt, stones and the like, but such stopper shall allow the entry of water.


35


3.19 Protection Against Damage in Transit

The ends of all pipes and specials shall be suitably covered, and protected against damage during transit with straw contained in hessian secured to the pipe ends. All flanges shall have wooden discs temporary bolted on. Pipes and specials shall be suitably supported so that no loads is taken directly on the external coating.

3.20 Jointing Ductile Iron Pipe

The jointing work for “push-in” or “mechanical” type of joint shall follow the following procedures unless otherwise approved by the Engineer. a) With “Push-In” Type Joint Jointing works shall proceed in the following order :

i) Lower pipes into the trench without damaging them ii) Remove all foreign material such as sand, mud, gravel, dirt and

paint flakes.

iii) Clean the rubber gasket and insert it into the socket in the following manner :

For Diameter Under 600mm

1) Form the gasket into a heart-shape, and insert the lower

portion of the gasket into the groove of the socket.

2) Insert the remainder of the gasket into the Socket Groove making sure that the projection on the inside of the sockets fits into the groove of the rubber gasket. The gasket shall not warp at any point.

3) Confirm that the gasket is seated correctly.

For Diameter Greater Than 600mm

1) Align the white marks of the rubber gasket with the marks on the face of the socket end and insert the gasket into the socket in the form of a clover-leaf.

2) Make sure that the projection on the inside of the socket

fits into the groove of the rubber gasket. The gasket shall not warp at any point.


36


3) Confirm that the gasket is seated correctly under the socket.

iv) Apply lubricant to the internal surface of the gasket. The type of lubricant used shall be of that approved by the Engineer.

v) Clean the external surface of the spigot end and apply lubricant to

the external surface of the spigot. Ensure that the lubricant covers the entire end to the first white line of the spigot.

vi) Align the spigot with the gasket and attach the jointing tools as

follows: For Diameter Under 150mm

1) Attach the wire rope and set the fork into position 2) Insert the spigot into the socket by pulling on the fork

For Diameter From 200mm – 600mm 1) Set the lever-block into the position. One (1) lever block

shall be sufficient. 2) Insert the spigot into the socket by pulling on the lever

block For Diameter From 700mm – 1200mm

1) Set the lever-block into position. Two (2) lever block shall be sufficient.

2) Insert the spigot into the socket by pulling on the lever

block

vii) When first of the two white lines marked around the spigot disappears into the socket, the jointing is finished.


37


b) With “Mechanical” Type Joint Jointing works shall proceed in the following order :

i) Make a bell hole the pipe socket and spigot to provide additional space for tightening bolts and nuts.

ii) Clean the external surface of the spigot

iii) Clean the gland and set the gland on the spigot

iv) Clean the rubber gasket and place it on the spigot. The gasket

shall be placed about 200mm from the end of the spigot.

v) Clean the internal surface of the socket and remove all foreign materials.

vi) Apply lubricant to the external surface of the spigot and the gasket

and to the internal surface of the socket. Ensure that the lubricant covers the entire end to the first white line of the spigot.

vii) Align the socket with the spigot and push the gasket into the

clearance between the spigot and the socket. viii) Centre the gland, align the bolt holes and insert the bolts at the top

and bottom then left and right side, tighten the bolts slightly.

ix) Insert the remaining bolts into the bolts holes and gradually tighten them.

x) Check tightness of all bolts and nuts with the use of a torque

wrench. Correct torque for bolts and nuts is specified in the following table :-

Tightening Torque of Bolts & Nuts for Mechanical Joint

Bolt Size

Torque (kgm)

Diameter of Pipe

(mm)

Recommended Average Handle

Length (mm) M20 10 100 – 600 250

M24 14 700 – 800 350 M30 20 900 – 2,600 450


38


3.21 Testing DI Pipelines 3.21.1 Test Pressure The test pressure to be applied shall be 15 bar at the lowest point. 3.21.2 Leakage Testing In testing, the main shall be filled with clean water and properly vented to

remove trapped air. After a period of 24 hours, the pressure shall be raised by pumping to the specified test pressure. Pumping shall then cease at 10 bar and after a period of 24 hours, pumping shall be resumed and the quantity required to be pumped, in order to restore the test pressure, divided by the time, shall be the measure of the rate of loss.

The length of main under test shall be deemed to have passed the test if the

leakage does not exceed 0.1 litre per mm of internal diameter per 24 hour per kilometre of pipeline per 30m of water pressure.

3.22 Marking of Pipes and Fittings

The following cast on or cold stamped marks shall appear on the socket end of each pipe :-

(a) The indicator that the pipe is of ductile iron DI. (b) The year manufacture (the last two digits) (c) The manufacturer's identification mark (d) The nominal diameter (ND) (e) The class designation ( 40, K9 or K12)

(f) The serial number (g) Standard reference (h) Initial SAJH in capital letter

In the case of fittings, these marks shall be placed on the body of each fitting

along with its main characteristics (ie. the angle of bend in degrees, the pressure rating of the flange etc.). For pipes and fittings having a spigot end for use with a `push-on' type joint, socket penetration lines (two white painted lines) shall be painted on the spigot end of the pipes and fittings.


39

SECTION 4.0 – POLYETHYLENE (PE) PIPES AND

FITTINGS



4.0 POLYETHYLENE ( PE ) PIPES AND FITTINGS 4.1 General

All pipes, specials and fittings must be of SAJH approved source and be to SAJH specifications (SAJH PS/PE/001) and (SAJH PS/PE/002).

4.2 Scope This Specification covers the supply of polyethylene (PE) pipes and

electrofusion couplers, tapping tees and fittings complying to the following Specifications :

(a) SAJH/PS/PE/001 – Polyethylene (PE) Pipes for Water Supply System. (b) MS 1058 : 1994 - Specification for PE pipes for water supply (c) Water Industry Specification 4-32-06 - Specification for Polyethylene

electro fusion couplers and fittings for cold potable water supply for nominal sizes up to and including 180. SEPT 1989: Issue 1

(d) Water Industry Specification 4-32-15 - Specification for PE 80 and PE 100

spigot fittings and drawn bends for nominal sizes up to and including 1000mm, March 1995 : Issue 1.

(e) DIN 16963 : 1980 Part 1 to 14 - Pipe joint assemblies and fittings for types

1 and 2 high density PE pressure pipes.

(f) British Standard BS 5750 : Part 2 (EN 29002)(ISO 9002) - Specification for production and installation 1994.

(g) SAJH refer to JKR 20200-0053-99 – JKR Tender Specification for PE

Systems for Water Supply. PE pipes to be supplied under this Contract shall conform with MS 1058 :

1994. All plain ended fittings for butt welding shall be made from pipes of the same pressure rating, dimensions, shape and performance, and shall comply with DIN 16963 : 1980. Electro fusion couplers, tapping tees and fittings shall conform generally with UK Water Industry Specification 4-32-06. Manufacturers shall preferably operate a quality system in compliance with BS 5750 : Part 2 ( EN 29002 )( ISO 9002 ).

4.3 Interpretation In compliance with existing standard nomenclature, references to " polyethylene or PE" shall infer both high density polyethylene (HDPE). SPECIFICATION FOR PIPEWORKS SAJH WS/PW/001 (Rev.1.0/06.2007) NO CHANGES ALLOWED WITHOUT THE PERMISSION OF QUALITY ASSURANCE DEPARTMENT OF SAJ HOLDINGS SDN BHD

40


4.4 Manufacturing Process All PE pipes and fittings shall be manufactured by manufacturers whose

product are certified by SIRIM or other approved institutions. They shall have adequate quality assurance systems related to the production of PE pipes.

The pipes shall be manufactured by an extrusion process using polyethylene material compounded by the material supplier. Plain ended segmental fittings shall be made by fabrication with the same PE pipes. Electrofusion couplers, tapping tees and fittings shall be moulded with the heating elements wires embedded in the bores of the fittings.

4.5 Polyethylene Materials The pipes and fittings shall be manufactured from polyethylene containing

only those anti-oxidants, UV stabilizers and carbon black necessary for the manufacture of the pipes and fittings to this Specification and to its end use including weldability. The material shall be compounded by the material supplier.

Mixing of master batch by pipe manufacturers is not permitted. No reworked

material shall be used in the manufacture of pipes and fittings including segmental fittings.

The materials shall be of type PE 80. The classification and compliance of the

material to the requirements of MS 1058 : 1994 shall be certified by an independent and approved testing institution.

Fittings not made of polyethylene shall be capable of withstanding the same

service requirements as the PE pipes. The material used for fittings shall be compatible with material used in the PE pipe system.

4.6 Dimensions The nominal outside diameter and wall thickness of the PE pipe corresponding

to the rated nominal pressures (PN) and the maximum working pressures shall be as shown in Table 4.1 unless otherwise specified.

The standard lengths of straight pipes shall be 9m for pipes above 125mm dia. The standard length of coils shall be 100m for pipes below 125mm dia.

PE pipes of outside diameter up to 125mm are allowed to be coiled. The

internal diameter of the coils should not be less than 25 times the nominal pipe outer diameter.

The tolerances on wall thickness and diameter of pipes shall be in accordance with MS 1058 :1994.The tolerances on length and standard weight of pipes shall be as shown in Table 4.2 and Table 4.3 :- The dimensions of fittings for butt welding shall be in accordance with DIN 16963 : 1980. The dimension of electrofusion couplers shall conform generally with WIS4-32-14.


41


The fittings to be jointed by electrofusion couplers shall have sufficient insertion length to reach the center of the couplers.

Table 4.1 Wall Thickness for PE 80 Pipes

Internal Wall Thickness (mm)Nominal Outside Diameter Diameter for PN 16 PN 12.5 Diameter (mm) PE Pipes (mm)(mm) Min Max Min Max PN 16 PN 12.5 16 2.0 2.3 - - 14 - 1620 2.3 2.7 2.0 2.3 15.4 16 2025 3.0 3.4 2.3 2.7 19 20.4 2532 3.6 4.1 3.0 3.4 24.8 26 3240 4.5 5.1 3.7 4.2 31 32.6 4050 5.6 6.3 4.6 5.2 38.8 40.8 5063 7.1 8.0 5.8 6.5 48.8 51.4 6375 8.4 9.4 6.8 7.6 58.2 61.4 7590 10.1 11.3 8.2 9.2 69.8 73.6 90

110 12.3 13.7 10.0 11.1 85.4 90 110125 14.0 15.6 11.4 12.7 97 102.2 125160 17.9 19.8 14.6 16.2 124.2 130.8 160180 20.1 22.3 16.4 18.2 139.8 147.2 180200 22.4 24.8 18.2 20.2 155.2 163.6 200225 25.2 27.9 20.5 22.7 174.6 184 225250 27.9 30.8 22.7 25.1 194.2 204.6 250280 31.3 34.6 25.4 28.1 217.4 229.2 280315 35.2 38.9 28.6 31.6 244.6 257.8 315355 39.7 43.8 32.2 35.6 275.6 290.6 355400 44.7 49.3 36.3 40.1 310.6 327.4 400450 50.3 55.5 40.9 45.1 349.4 368.2 450500 - - 45.4 50.1 - 409.2 500560 - - 50.8 56.0 - 458.4 560630 - - 57.2 63.1 - 515.6 630

4.7 Flanged Connections All flanges shall be to PN16 pressure rating and dimensionally similar to BS

4504 : : 1989 Table 11. Each set of flange connection shall be supplied complete with gaskets, nuts, bolts and washers. The flange, nuts and bolts shall be protected with not less than 200 microns thick coating of Fusion Bonded Epoxy Powder. Washers shall be hot dipped galvanised.


42


Table 4.2 Permissible Variations for Pipe Lengths

Permissible Variation

Coiled Bundles, Unwound Length +1%

- 0%

Straight Length up to and Including 6m +10mm

- 0mm

Straight Length of above 6m +20mm

- 0mm

Table 4.3 Permissible Variation For Weights

Permissible Variation

For an individual pipe 8% by wt.

For a batch of 100 pipes 5% by wt.

For coil bundles 5% by wt.

4.8 Works Tests The following tests on the pipe samples shall be conducted, all in accordance

to MS 1058 : 1994 (i) Dimensions (ii) Surface finish and marking (iii) Pressure test 165h, 80° C (iv) Thermal stability (v) Longitudinal reversion 4.9 Packing Loose parts such as couplings, flanges, bolts and nuts, rubber rings and

gaskets shall be packed in weather proof crates with the identification of the Consignee and the contents labelled.


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4.10 Handling, Transportation and Storage 4.10.1 General Polyethylene is a tough resilient material which is relatively light and easy to

handle. However, it is prone to damage by scoring with sharp objects. Therefore, careful handling is always required. They shall not be dropped or dragged or subjected to rough handling particularly during loading and unloading operations.

4.10.2 Handling and Transportation For transportation bulk loads, the vehicle used shall be provided with a clean

flat bed, free from nails or other hard projections which may cause damage. If high sided lorries are used, special care shall be taken to prevent slippage or excessive bowing of the pipe. All sharp edges shall be adequately padded up.

Care shall be taken to avoid positioning pipes and fittings near or adjacent to

exhaust pipes or other heat sources. The pipes and fittings shall not be transported or stored together with diesel oil or sharp edged equipment in order to avoid contamination or damage.

Straight pipes shall be fully supported and bound together with non-metallic

ropes. The pipes shall not rest on the sockets of other pipes or pipes fitted with couplers.

The pipes shall not be coiled to less than 25 times the outside diameter of the

pipes. When transporting the pipes of different classes, pipes of lower pressure class

shall be stacked above others of higher class. If transported together, coiled pipes shall be placed on top of straight pipes. If the pipes are transported one inside another, the smaller pipes shall be removed first and laid out.

Damage to pipes and pipe ends shall be avoided during lifting, particularly

pipes with couplers. When lifting by crane, rope or canvas slings shall be used for straight pipes.

If PE pipes are handled with mechanical lifting devices, the pipes shall be

suitably protected to prevent scoring. Any scoring on the pipe surface that are more than 10% of the wall thickness shall cause the pipe to be rejected or else the section shall be cut out. A depth gauge shall be used for measurement.

Coiled pipes whether strapped or on pallets are easily handled by forklift.

Pipes shall NOT be rolled off the edge of loading platforms or trailers. Either slings or a forklift with suitably protected boom attachments shall be used to unload them. Coils shall be stored horizontally.

Uncoiling shall be done so that the pipe leaves the coil tangentially (in the

direction of the pipe coils) to avoid kinking and twisting of the pipe.


44


4.10.3 Storage Coiled pipes shall be stored on a firm, flat surface and to a maximum height of

two metres to prevent distortion to the bottom convolutions. Coils shall be tied at intermittent points and as a complete coil to prevent slippage and distortion within the coil.

Where storage facilities necessitate the material to be exposed externally, the

pipes shall be properly covered up. Adequate space shall be allowed for lifting machinery to manoeuvre around

the pipe stacks without causing accidental damage to the pipes. Where individual pipes are laid out and stacked to a triangular form,

deformation may occur to the pipes in the lower layers, particularly during warm weather. Such stacks shall therefore be not greater than one metre high. Socketed or coupled pipes shall be stacked with the sockets at alternate ends and with the sockets protruding to avoid uneven stacking which may permanently distort the pipes.

At all times pipes and fittings shall be stored away from exhaust outlets and

all other high temperature sources. Care shall be taken to avoid contact with lubricating or hydraulic oils, gasoline, solvents and other aggressive chemicals.

The pipe storage areas shall be provided with adequate access for construction

vehicles and/or lifting equipments. 4.10.4 Precautions Sharp sections which could cause indentation or scoring to the pipes shall not

be allowed to bear against the pipes. Pipes pre-assembled with fittings or flanges shall be stacked or supported so

that the ends are free from loading and protected from damage. Pipes cut and squared for butt fusion shall be handled with the utmost care to keep the pipe ends from damage, particularly during transportation.

Straight pipes stacked for storage or transportation shall be supported

continuously and evenly to minimise distortions. Padded supports of at least 75mm bearing width at spacing not greater than one metre centres may be placed beneath to support the pipes.

During coiling and uncoiling care should be taken to maintain the coil

diameter to the specified minimum of 25 times the outside diameter to prevent kinking.

4.11 Electrofusion Couplers and Tapping tees The fittings shall be free from cracks, voids, blisters, distortion, dents,

inclusions or other defects likely to impair their performance. For each size and type of fitting, the fusion time inclusive of cooling time at a


45


given voltage shall be specified by the fitting manufacturer. It shall be the same for all pipes to be joined to that fitting irrespective of the pipe SDR and material.

The nominal resistance of the heating elements and production tolerances for

each type of fittings shall be declared by the fitting manufacturers. All fittings shall have mechanically shrouded male electrical terminals. The maximum power requirement and voltage range for all the fittings shall be to the fittings manufacturer's Specification.

A permanent and obvious means of indicating that the joint has been subjected to the fusion cycle shall be provided on the external surface of the fitting, eg fusion or melt indicator. All electrofusion fittings shall not be removed from its packing until fusion jointing is ready to be conducted. This include scraping, trimming and getting pipe ends and surfaces prepared.

Straight couplers and Elbows shall incorporate a means of preventing pipe

penetration beyond the socket.The means shall not prevent use of the couplers with longitudinally restrained pipes in repair situation i.e. it shall be possible to slide the coupler onto one pipe far enough to allow the pipe ends to be aligned and the movement of the coupler reversed until it overlaps both pipe ends in position to be joined.

For Reducing couplers there shall be no sudden step changes of internal

diameter and incorporate a mean of preventing pipe penetration beyond the smaller socket.

For Transition Coupler and Elbow, the fittings shall incorporate a female

internally threaded brass/stainless steel socket on one end for connection to existing threaded GI meter standpipes.

For In-line tees and associated spigots, the fitting shall incorporate means of

controlling pipe penetration with the socket such as to prevent obstruction of the tee outlet.

Tapping Tees shall be capable of installation by using an underclamp. The

tapping tees design shall be easy to removed and replaced from an above ground position. They shall be capable of passing all hydraulic testing required of the fittings without additional fastenings or constraints to the cap.

Tapping tees shall have built-in cutting device to cut through pressurized PE

pipes without allowing uncontrolled leakage of water to occur. The manufacturer shall declare the allowable operating torques to be applied for the cutting device. The cutting device shall have a socket key recess to be operated by a suitable key with no thread follower. The fittings integral heating element shall be clear of the path of the cutter. The fusion sealing width, i.e. the distance between the inner and outer turns, at any point shall not be less than 15mm.

The design of the tapping tees shall include provision for pressure testing of

the connected service pipes and the fusion interfaces between the pipes and fittings without removal of the cutter prior to tapping the main.


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4.12 PE Compression Fittings The compression fittings shall be suitable for quick jointing of PE pipes

system. Pressure rating for fittings of 16mm to 110mm NOD shall be up to 16 bar.

The whole fittings shall be manufactured from resistant thermoplastic resins

of polypropylene type. Dimensions shall generally be in accordance with DIN 8076 and BS 5114 1975. The fittings and the manufacturers shall be approved by the S.O. before ordering.

4.13 Examination of Pipes and Fittings The ends of PE pipes and specials shall be cleaned by water and any

damaged portion cut-off and removed before butt or electrofusion can be allowed to proceed. Electrofusion fittings shall not be removed from their packing before use.

Should any pipe or special are found to be damaged, it shall be excluded

from the work until repairs have been carried out to the satisfaction of the S.O. In general no MS pipe shall be laid if an end has suffered distortion from the circular and a mechanical coupling or socket cannot be fitted or, if damage to the internal and/or external protection has not been satisfactorily repaired.

All PE pipes with deep cuts to the pipe wall, measured by a depth gauge of

suitable accuracy approved by the S.O., of more than 10% of the pipe wall thickness shall not be laid until that damaged section of the pipe has been satisfactorily cut out on the Contractor's own expense unless the damages have been recorded during take over at Central store. All PE pipes and fittings outer diameter and roundness shall be measured by approved `PI' ruler supplied by the Contractor.

4.14 Laying PE Pipes The pipes or specials shall be inspected by the S.O. or his representatives

for deep cuts or scratches, which are deeper than 10% of the pipe wall thickness. The depth shall be measured with approved depth gauges of suitable accuracy supplied for the sole use of the S.O. or his representatives by the Contractor. All damaged or flawed section of pipes shall be cut out and removed to the satisfaction of the S.O. before jointing according to Clause 4.13.

The pipes and specials shall be jointed by automatic butt or electro fusion welding to form a string above ground and shall be supported by smooth rollers support of a design approved by the S.O. Three standard lengths of pipe on each side of the fusion machine shall have a minimum of two (2) roller supports per length of pipe. All fusion joints shall be inspected and assessed with joint record printouts from the automatic butt or electro fusion machine. All joints shall be approved by the S.O. or his representatives before the Contractor is allowed to proceed with pipelaying


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works. The maximum pulling length of fusion jointed PE pipes into position alongside or directly into pipe trench after fusion jointing shall not exceed 300m or length limited by the hydraulic actuator of the automatic butt fusion machine. Dragging on ground surface is strictly prohibited. All jointing of specials, tees closing lengths etc to be conducted in the trench shall be by automatic electrofusion couplers or other electrofusion fittings.

The trench bottom shall be free from all rocks, boulders, stones or hard

particles which may damage the pipe walls. Before any pipes or specials are lowered into the trench, the pipes and specials are to be rechecked for deep cut and scratches described above and the fusion joints cooled sufficiently (specified cooling time for the last joint has elapsed) before stress is imposed upon any premade joints. When lowering pipe into trenches, care should be taken to avoid scoring of the pipe by contact with the sides and bottom of the trench. Special care shall be needed when passing under/around obstruction or other utilities. Pipe roller supports for the first four lengths of pipes from the pipe end to be lowered into the trench shall be provided. Cut section of rejected or damaged PE pipes, planks and rope shall be used for protecting the remaining pipes where appropriate but wire ropes or chains shall not be used.

The trench bottom shall be bedded with well graded free flowing granular

sand that is free from stones or hard particles larger than 6mm diameter. Gradual changes in direction can be accommodated by pipe deflection but the pipe shall not be cold bent to a radius smaller than twenty-five(25) times the outer diameter of the pipe. Under no circumtances shall hot bending in any form be allowed on site. A minimum distance of 300mm from obstruction and other services shall always be maintained. The pipe shall be kept as central as possible within the trench to enable correct side-fill compaction but some snaking to compensate for thermal expansion of the pipe will be allowed.

Pipes and specials to be embedded in concrete shall be firmly held in

position and protected from damage during pouring or compaction by a heavy duty polyethylene sheet. Should any pipe or specials become either partially or wholly clogged before final acceptance of work, it shall be cleaned out or replaced by the Contractor at his own expense.

After laying the interior of pipes or specials shall be carefully cleaned to

remove any debris, dirt, stones or other matter that may have entered during laying.

Except when work is proceeding, all open ends of pipes and specials in the

trench shall be kept closed by means of a fine wire gauge, wooden stopper or other approved means to prevent the entry of dirt, soil, stones and the like, but shall allow the entry of water.

4.15 Welding PE Pipes

All PE pipes shall be jointed by fully automatic butt fusion welding equipment. All PE pipes specials and tapping saddles shall be jointed by fully automatic electrofusion equipment. All automatic fusion equipments shall have joints data retrieval facility allowing joint records to be retrieved


48


and printed. A printer for each fusion machine used on site shall be supplied to the S.O. for his sole use. An electronic data transfer unit suitable for use with the Butt and Electrofusion machines to transfer all joints data to a computer shall also be provided by the Contractor for the sole use of the S.O..

The full set of Automatic Butt Fusion welding machine shall comprise the

following :

(a) Chassis and Clamps which are sufficiently robust to accurately align the pipe to be jointed and have insert rings to fit different pipe diameters up to 315mm nominal outer diameter.

(b) Hydraulic/Pneumatic Unit capable of actuating the clamp unit to

provide adequate force and speed of operation for pipes diameter up to 315mm nominal outer diameter. The pressure required shall be automatically set and calculated by the control box.

(c) Trimming/Planning Tool capable of being mounted securely within

the frame of the jointing machine, to prevent twist during trimming and planning to produce accurately matched planed surface.

(d) Electrically operated heating plate with temperature controller for a uniform temperature range of between 200 to 220 deg. C. The plate shall be uniformly coated with teflon having adequate release properties and fitted with an accurate temperature probe using a digital thermometer.

(e) Control Box designed to carry out the operations automatically for

pipes diameter up to 315 nominal outer diameter with the following facilities :

(1) Automatic interlock of the entire joint cycle with correct heater temperature;

(2) Ambient temperature compensation at bead-up; nominal dwell

time less than two seconds; constant monitoring of pipe slippage;

(3) Automatic monitoring of cooling cycle; (4) Identification of real time; date; job and operator for every joint; (5) Pipe selection programme specific to material type; diameter and

SDR rating; (6) Automatic recognition of dual pressure welding conditions for

thick wall pipes;


49


(7) Complete data retrieval facility for all joints via a data printer or electronic transfer to comply with BS 5750:Part 1 4.9.2 on special processes;

(8) Audible alarm to alert operator at critical stages.

(f) Portable Generators of brushless alternator construction complete

with voltage stability consistent with TIN-12 specification: alternator to be capable of providing a 10% overload facility. Generators to be rated to the appropriate fusion application and the equipment as specified by the manufacturer

The Butt Fusion jointing procedure shall be as follows :-

(1) Cleaning of the trimming tool and the Heater plate. The trimming tool shall be cleaned with water and lint free

materials. The heater plate shall be cold when cleaned with soap and water and lint free materials. The heater plate shall be cleaned at the start of each working day by making a dummy joint. The joint shall be cut-off before actual jointing work is conducted.

(2) Trimming of pipe ends. Before trimming, the pipe ends shall be wiped clean on both

the inner and outer surfaces to remove mud or dust with a damp cloth. The pipe ends shall then be cut square to remove any embedded hard particles or stones using a universal or other approved PE pipe cutter. The pipe shall be dry prior to proceeding. The pipes shall then be positioned in the clamps with pipe makings aligned. This will assist in obtaining best match in diameter. The pipes clamps are then tightened to grip and reround the pipes. The pipe ends shall then be trimmed and planed with the trimming tool mounted onto the machine until continuous shavings are produced from each pipe end.

Bevel and clean outer and inner edges of loose shavings and check the pipe end for alignment. The pipe ends trimmed surface shall not be touched or handed to prevent contamination of the clean surfaces before fusion.

The pipe ends shall not have any visible gap when the ends are brought together. The maximum outside diameter mismatch of the pipe ends, measured by a depth gauge, shall not be more than 10% of the pipe wall thickness when the pipe ends are brought together for pipes up to 315 NOD. If the mismatch is greater, the pipe shall be realigned and replanned until permitted tolerance is obtained.

(3) Automatic jointing The operator shall check that the machine is levelled with appropriate levelling apparatus, input operator code, identify pipe materials and diameter and after inspecting trimming start


50


the automatic fusion cycle. All joints shall be assigned a number and shall be marked on the pipe by suitable marker approved by the S.O. and also recorded on drawings. A log book recording joints data shall be kept by the Contractor on site for the inspection of the S.O. or his representatives.

The full set of Automatic Electrofusion machine shall include the following;

(1) Automatic Electrofusion Control Box capable of operating in a fully automatic mode compatible with the integral heating elements of all electrofusion fittings for pipes up to 315mm nominal outer diameter used in this Contract. There shall be a complete data retrieval facility for all joints to be undertaken via a data printer or a data transfer unit.

(2) Potable Generator as specified for the automatic butt fusion machine.

The generator shall be rated to the appropriate electrofusion application as specified by the manufacturers of the fittings.

(3) Universal main alignment and restraint clamps units with insert rings

for pipe sizes up to 315mm nominal outer diameter, multi-functional for couplers, elbows and tees.

(4) Alignment and restraint underclamp bottom-loaded saddle kits and G-

clamps for pipe sizes up to 315mm nominal outer diameter.

The Electrofusion jointing procedure shall be as follows:- (1) Trimming of pipe ends square axis and any burrs removed. Check

pipes and fittings for correct fit into couplers. If the pipes are found to be too oval to fit into couplers, the pipes shall be rerounded by on approved mechanical pipe rerounding tool or a straight length of suitable round pipe be fused onto the end before jointing.

(2) Clean pipe ends and prepare pipe ends with universal scraper or

approved surface preparation tool capable of removing the oxidised surface of the pipe ends for length in excess of insertion depth. For tapping tees and saddles the general area in excess of the saddle base area shall be cleaned to the satisfaction of the S.O. The tool shall remove a layer 0.2 – 0.4mm thick from the outer surface preferably as a continuous strip of swarf over that length and round the pipe or for the full area of saddle base. Hand scrapers of the Harris type’ or equivalent are allowed for tapping tees and saddles.

The prepared area shall then be cleaned with acetone or other approved solvent. The prepared pipe surface shall not be handled or contaminated prior to welding.


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(3) The electrofusion fittings or tapping tees shall be removed from packaging and degreased with acetone or other approved solvent prior to insertion to pipe ends or clamp onto pipe. The insertion depth is than marked by suitable marker by inserting the couplers/fittings up to the center stop.

(4) Using correct sized pipe clamps or saddle clamps, secure the pipe

fittings. The alignment and gaps between the pipes and fittings shall be checked by depth gauges. The total gaps between the pipe outer diameter and fittings shall not exceed 2% of the pipes nominal outer diameter. The fittings shall be adjusted with suitable wedges, if required, to axially align the pipes centrally in the fittings.

Electrofusion shall then only be allowed to proceed after

complying with the above checks.

(5) On completion, the melt indicators of the fusion fittings should appear. If there is no apparent movement of the melt indicators, the joint shall be cut out and a new joint be made.

(6) The joint shall be left in the clamps for the cooling time specified

for the fittings or tapping tees.

(7) The main shall not be tap with the integral built-in cutter until the joints or saddles have been approved by the S.O.

4.16 Payment for PE Pipe Joints The Contract Rates for making internally and externally welded slip and collar

joints, PE Butt and Electro Fusion joints shall cover the cost of providing, operating and maintaining all services, plant, equipment, fuels, materials of all kinds, apparatus of all types and everything necessary for air testing, making good and/or completion of internal lining and external coating, protecting pipe ends and completing external protection of the welded joints , repair to PE pipes and all as specified.

4.17 Testing PE Pipelines The test pressure to be applied shall be 1.5 times the rated pressure with

details shown in drawings or as directed by the S.O.. In testing, the main shall be filled with clean water at a steady rate to enable

all high points to be properly vented to remove trapped air to the approval of the S.O. The filled pipeline shall then be stood for a minimum of 12 hours before water is added to replace collected air. The pressure shall then be raised to the specified test pressure by pumping continuously at a constant rate. The pressure rise with respect to time and volume pumped shall be recorded and monitored. The pressure rise response during this pressurisation phase shall be approximately linear indicating acceptable amounts of air in the system. If this initial analysis indicate that significant volumes of air is still trapped in the system, the test shall be terminated and


52


air bleeding at all high points and the end of the test section shall be reconducted prior to the continuation of the test.

After the specified test pressure has been reached, the test length shall be allowed to stand without make-up pressure and the pressure is allowed to decay over time for one hour. The pressure at the end of the one hour period is noted and the pressure is then reduced to 1.3 times the rated pressure and the pressure is then pumped up again to 1.5 times rated pressure.

When the specified test pressure has been attained, the pump shall be

stopped and pressure recorded at 10 mins interval for two (2) hours or until the entire tested length of the pipeline and joints has been inspected whichever is longer.

The length of pipelines under test shall be deemed to have passed the test if

no visible leakage occurs at all exposed welds and joints and the average rate of pressure drop at any stage during the two (2) hours test period or longer does not exceed 10 per cent of the specified test pressure per hour.

To avoid high ambient temperatures and sudden cooling of pipeline during

test causing fluctuation in pressures, testing shall be arranged to be conducted in the cooler hours of the day, early morning or late evening.

4.18 Markings

All pipes and fittings supplied shall have at least the following information:- (a) Manufacturer's identification (b) Dimensions ( nominal outer diameter ) (c) Material supplier and material class (PE 80) (d) Nominal pressure class (PN) in bar (e) Production period (date or code) (f) Number of this Specification ( MS 1058 )

(h) ‘SAJH’ lettering (i) Batch production number

In addition all segmented butt welded fittings shall bear the diameter of the branch, in the case of tees, and the angle, in case of bends and any angled branches on the outside of the pipes and fittings.

The markings shall be made only on those pipes and fittings that have

satisfied all tests and other requirements of this Specification.


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SECTION 5.0 –

uPVC PIPES AND FITTINGS



5.0 uPVC PIPES AND FITTINGS 5.1 General

All pipes, specials and fittings must be from SAJH approved sources and be to SAJH specifications (SAJH PS/PV/001)and (SAJH PS/PV/002).

The uPVC pipes and fittings to be supplied shall be of classes C, D or E as specified in the Bill of Quantities and shall be of SAJH approved as in Specification

Subject to the specified requirements of this Section, the plain ended pipes shall be manufactured in accordance to MS 628:1982. The bellmouthed pipes, with one ended bellmouthed and one plain ended shall be manufactured in accordance to MS 628:1982 and BS 4346 Part 2:1970. uPVC joints and fittings shall be manufactured in accordance to BS 4346 Part 1:1969 and BS 4346 Part 2:1970.

The bellmouthed socket shall be manufactured in accordance to MS 923 Part 3 or BS 4346 Part II. The pipes shall conform to the standards as stated unless specifically or otherwise stated in this specification.

5.2 Materials used in Manufacture

The material used in the manufacture pipes, joints and fittings shall consist substantially of polyvinyl chloride, to which may be added only those additives that are needed to facilitate the manufacture of the polymers, and the production of finish, mechanical strength and capacity.

None of these additives shall be used separately or together in quantities sufficient to constitute a toxic hazard, or to impair the fabrication or welding properties of the pipes, joints and fittings in particular long term mechanical strength and impact strength.

The addition of the manufacturer’s own rework material produced during the manufacture and works testing of pipes, joints and fittings complying with this specification is permissible. No other rework material shall be used.

The dispersion of all ingredients in the material composition shall be informed. If tin stabilizers are used for joints and fittings, these shall be only dialkyl tin C4 and higher homologues. When tested by method 120B of BS 2782 (Methods of Testing Plastics), the deformation temperature of the material under load shall not lower than 75 degrees Centigrade.

5.3 Colour The colour of the pipes shall be blue. SPECIFICATION FOR PIPEWORKS SAJH WS/PW/001 (Rev.1.0/06.2007) NO CHANGES ALLOWED WITHOUT THE PERMISSION OF QUALITY ASSURANCE DEPARTMENT OF SAJ HOLDINGS SDN BHD

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5.4 Classification

The pipes, joints and fittings shall be classified in accordance to the Maximum Permissible Working Pressure as in Table 5.1.

Table 5.1 – Classification of uPVC Pipe

Maximum Permissible Working Pressure

Class of pipe

At 20 deg. C

At 30 deg. C

C

D

E

9 bar

12 bar

15 bar

7.2 bar

9.6 bar

12.0 bar

5.5 Thickness and Diameter

The pipes shall be designated by the nominal size and shall conform to the outside diameters and wall thickness given in table A.

5.6 Tolerance and Dimensions

Mean tolerances on outside diameters shall conform to the requirements of Table A. An out of roundness tolerance of + / - 0.55 percent on mid mean outside diameter is permitted. A tolerance of +3mm –10mm shall be allowed on the length of an individual pipe but the total length of pipe supplied shall be not less than the total length ordered.


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Attachment Table A

Nom. Size

(mm)

Mean Outside Diameter (mm)

Out of Roundness

(Ovality) (mm)

Wall Thickness (mm)

PN 12 PN 15 Ave. Individual

Value Average Individual

Value min max min max max min max max min max 10 17.0 17.3 17.0 17.3 - - - 1.9 1.5 1.9 15 21.2 21.5 21.2 21.5 - - - 2.1 1.7 2.1 20 26.6 26.9 26.6 26.9 - - - 2.5 1.9 2.5 25 33.4 33.7 33.3 33.8 - - - 2.7 2.2 2.7

32 42.1 42.4 42.0 42.5 - - - 3.2 2.7 3.2 40 48.1 48.4 48.0 48.5 - - - 3.7 3.1 3.7 50 60.2 60.5 60.0 60.7 - - - 4.5 3.9 4.5 65 75.0 75.3 74.8 75.5 - - - 5.5 4.8 5.5

80 88.7 89.1 88.4 89.4 5.3 4.6 5.3 - - - 100 114.1 114.5 113.7 114.9 6.8 6.0 6.9 - - - 125 140.0 140.4 139.4 141.0 8.3 7.3 8.4 - - - 155 168.0 168.5 167.4 169.1 9.9 8.8 10.2 - - -

175 193.5 194.0 192.8 194.7 11.4 10.1 11.7 - - - 200 218.8 219.4 218.0 220.2 11.6 10.3 11.9 - - - 225 244.1 244.8 243.2 245.7 12.9 11.5 13.3 - - - 250 272.6 273.4 271.6 247.4 14.3 12.8 14.8 - - -

300 323.4 324.3 322.2 325.5 17.0 15.2 17.5 - - - 350 355.0 356.0 353.7 357.3 18.6 16.7 19.2 - - - 375 405.9 406.9 404.3 408.5 21.1 19.0 21.9 - - - 400 456.7 457.7 454.9 459.5 23.8 21.4 24.6 - - -


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5.7 Length The standard length of pipes shall be 6 metres.

The manufacturer may supply not more than 10 percent of the order in lengths decreasing by multiples of 150mm, provided than the minimum length of any pipe shall be not less than 3.4 metres. The ends of the shortened pipes shall be cut and turned to the correct dimension for jointing.

The contractor shall supply free of charge the extra joints required due to the supply of non-standard pipes.

5.8 Appearance

The wall of pipes, joints and fittings shall be homogenous throughout and the internal and external surface shall be clean, smooth and reasonably free from grooves, blisters, wrinkles, dents, heat marks and other defects that would impair their performance in service.

5.9 Joints

The pipes to be supplied shall have an integral bell-mouth socket formed on one end for mechanical rubber ring joint conforming to the relevant sections of BS 4346 Part 2.

The plain end of the pipes shall be chamfered to facilitate insertion during jointing.

A witness mark should be put in on the cut end of the pipe.

Rubber ring shall be factory fitted in the ring housing of the pipe by the manufacturer in the correct way as to specification unless otherwise stated.

The rubber ring shall have the retaining capabilities to hold itself in the housing without causing displacement during handling, storage and installation of the pipe. The rubber ring shall be of type: a) The type which employ compression sealing system b) The type which employ a combination of lip compression sealing system The uPVC coupler joints shall be suitable for use with plain ended uPVC pipes. Each coupler joint shall consist of a uPVC sleeve suitable for jointing two rubber rings set in plain grooved ends. The rubber rings shall be manufactured of natural rubber complying with the requirements of Type 1 of BS 2494 Part 1 (1976). The completed joint shall be watertight when the pipes are deflected at angles up to 5 degrees and subjected to (3.6 +/- 0.1) times the Maximum Permissible Working Pressure specified.


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5.10 Pipe Seal

The seal shall consists of flexible of rubber element of effectively seal against the spigot and socket, and a reinforcing plastic element bonded to the rubber element to hold the seal firmly. The seal material shall be EPDM rubber in 60 +/- 5 IRHD hardness and meets the requirement of ASTM F-477 and EN 681-1. The material is approved for contact with cold potable water as in BS 6920 Part 1. Depending on the request of the client, seals can be supplied either fitted in the pipe groove or separately in a proper sealed packaging boxes to retain the quality of the seals over a long period. Each seal shall be marked with pipe dimension, manufacturing period and relevant standards used in the manufacturing. The rubber ring shall have the retaining capabilities minimum of 5 kgf for ND 100mm and below and 9 kgf for sizes ND 155mm.

5.11 Test Requirements 5.11.1 Obligations

The supplier shall give the S.O fourteen (14) days notice in writing of date on which any of the samples will be ready for testing or inspection at the place of manufacture or at an approved laboratory. The S.O shall attend the appointed place within the said fourteen days or the test may proceed in his absence. The supplier shall in any case submit to the S.O within seven days three certified copies of the test readings.

5.11.2 Routine Tests

For routine tests, the S.O or his representatives shall have access at all reasonable times for inspection and testing of the pipes being ordered by SAJH. The manufacturer at his own expense, supply and maintain in proper condition all necessary dimensional gauges, prepare the necessary test pieces, appliances and supply labour for test specified. All tests shall be done prior to delivery.

5.11.3 Type Tests

The supplier shall either provide the necessary facilities and a qualified chemists to carry out their test at the factory or retain the services of an independent testing authority approved by the client.


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Copies or Type Test Certificates shall be submitted to the S.O for inspection. All expenses incurred in carrying the Type Tests at the factory or by an independent testing authority shall be borne by the Supplier. The S.O reserves the right to collect test samples from the factory forward to an independent testing authority for test. The costs of such additional tests shall be borne by the Supplier.

5.11.4 Sampling

The number of sample to be tested by the Supplier at his own expense shall be selected in proportion to the number of pipes each size and class of production within the same day of 24 hours. Test shall be carried out not earlier than 15 hours after the pipes have been extruded. The proportions described are as Table 5.3.

Table 5.3 – Testing Proportion

Tests Proportion Routine Test Heat reversion Resistance to Acetone Short-term Hydraulic Impact Strength @ 20° C Type Test Resistance to Sulphuric Acid Impact Strength of 0 deg. C Opacity Effect on Water Long-term Hydraulic

Not less than 1 sample per 50 pipes from production within same day 24 hours -Ditto- -Ditto- -Ditto- One complete test each once a year for each Formulation used, or whenever a change is made in the formulation or method of manufacture of the pipes whichever is move often.


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5.12 Routine Tests 5.12.1 Heat Reversion Test on uPVC Pipes

Heat Reversion Test shall carried out as described in Appendix ‘A’ to MS 628:1982. The change in the length of the sample between the scribed mark shall nor exceed 5.0 percent and the sample after testing shall show no faults such as cracks, cavities or blisters. A specimen shall be taken from each machine at least once in every 8 hours running, and shall meet the requirement specified.

5.12.2 Resistance to Acetone Test on uPVC Pipes

Resistance to Acetone Test shall be carried out as described in Appendix ‘B’ to MS 628:1982. The sample shall show no declamination or disintegration. Flattening and/or swelling of the sample shall not be deemed to constitute failure. A specimen shall be taken from each machine at least once in every 8 hours running and shall meet the requirements.

5.12.3 Factory Hydrostatic Test on uPVC Pipes

When tested by the method described in Appendix ‘G’ to MS 628:1982 the pipes shall withstand the appropriate Factory Hydrostatic Test pressure for at least 1 hour without failure as shown in Table 5.4.

Table 5.4 – Factory Hydrostatic Test Pressure

Class

Nominal size of pipes

Min. 1 hr interval Factory Hydrostatic Test Pressure

(bar)

C

D

E

All sizes

All sizes

All sizes

32.4

43.2

54.0

One specimen shall be taken at random from each machine at least once every 8 hours running or once in every 300 metres run, whichever is the greater quantity of pipe and shall meet the requirement.

5.12.4 Impact Strength Test at 20 degrees C on uPVC Pipes.

Impact Strength Test at 20 degrees C shall be carried out as described in Appendix ‘F’ to MS 628:1982.


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Initially, sufficient specimens shall be taken at random from each machine so that at least one is taken per shift and at least 14 strikes made per extrusion run. If no specimen fails (defined as fracturing or cracking through its complete wall thickness), no further test specimens need to be taken. If of the initial 14


strikes, one, two or three specimens fail, further specimens shall be taken at random and tested to ensure a total of at least 42 strikes. If during the test, more than four specimens fail the test shall be discontinued.

A batch is defined as a continuous extrusion run of one size and class of pipe from one extrusion compound up to a maximum of 8 hours duration. If the first 14 strikes cause no failure fracturing or cracking the pipes represented by the specimen shall be deemed to comply with the specification. If the first 14 strikes cause four or more failure the pipes represented by the specimens shall be deemed not to comply with the specification. If because of one, two or three failure, it is found necessary to increase the number of strikes to 42, the pipes represented by the specimens shall be deemed not to comply with this specification if out of the 42 strikes five or more failures occur.

5.13 Compliance

Should the first cycle of any Routine Tests specified in clause 5.12.1 to 5.12.4 of this specification fail to satisfy the requirement specified, then the whole batch of 50 pipes represented by the sample shall deemed not to comply with this specification and shall be rejected.

5.14 Method of Rejection

All pipes shall be serially numbered and have its serial number indelibly marked on the barrel so that pipes of any batch of fifty or part of it, manufactured within the same 24 hours which do not comply with this specification can easily identified and rejected. If series of pipes numbered from A 0001 to A 1800 the test on sample pipes of serial number between A 0201 to A 0250 inclusive fail to comply with tests specified in this specification then all the pipes bearing serial number between A 0201 and A 0250 inclusive shall be rejected.

5.15 Marking of Pipes and Fittings

All pipes and specials supplied shall have at least the following information:- a) The manufacturer’s distinguishing mark b) The nominal size and class c) The letters SAJH (at least 75mm high) d) The date or the last two digits of the year of manufacture e) The serial number of pipe f) Standard reference

Adhesive labels will not be accepted. The colour of markings shall be dark blue. SPECIFICATION FOR PIPEWORKS SAJH WS/PW/001 (Rev.1.0/06.2007) NO CHANGES ALLOWED WITHOUT THE PERMISSION OF QUALITY ASSURANCE DEPARTMENT OF SAJ HOLDINGS SDN BHD

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5.16 Test Certificates

The supplier shall submit the Test Certificate to the S.O copies of all test results, which have been performed on pipes to be supplied.

5.17 Delivery

Pipes made of this material are light and very easily damaged if it is not handled with care. When loading socket and spigot pipes, these should be stacked in alternate layers so that the sockets do not carry any load. Pipes should be loaded on a vehicle in such a way that the overhang is not more than 1 metre.


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SECTION 6.0 – PIPELAYING



6.0 PIPELAYING 6.1 Closing Lengths The use of closing lengths for pipes shall be avoided by laying the pipes in a

continuous length. However, where this proves impossible the Contractor shall use the special 'sized' pipes for cutting to the exact lengths required. These steel 'sized' pipes manufactured truly circular along their full length shall be marked by two longitudinal bends in paint along each pipe. Closing lengths shall be located as near to access openings as possible so as to enable internal and external welding at joints to be carried out.

PE pipes shall be measured and cut to suit site and temperature condition

before being fusion jointed to the approval of the S.O. Closing length required to be jointed in trenches shall be jointed by electrofusion couplers.

6.2 Pipe Cutting Where it is necessary to cut pipes to provide closing lengths or for laying

pipe specials or in the repair of damaged or chipped pipes, the cutting shall be neatly and accurately performed by skilled personnel so as to leave the end of the pipe truly normal to the axis of the pipe.

PE pipes shall only be cut by a universal pipe cutter or equivalent to the

approval of the S.O. or his representatives.

6.3 Welding Personnel Only the most highly skilled welders shall be employed on the Works. Every

MS pipe welder before commencing any joint welding shall prepare specimens for testing in accordance with BS 4515 for each welding procedure proposed by the Contractor. Every welder shall be tested in accordance to BS 4515. The Contractor shall be responsible for the preparation, setting up, provision of specimen, all necessary equipment and materials for the testing of welding personnel.

Only trained PE welders shall carry out butt or electrofusion welding. The

Contractor is required to show proof of the competency of their PE welders in form of certificates from pipe manufacturers or Gas Malaysia Sdn Bhd in using the specified automatic machines for butt and electrofusion jointing. The welders are required to do a welding test on site to demonstrate their expertise.

The S.O. will advise the Contractor in writing which welders pass the

performance qualification test. Each welder will be assigned an operator reference number and only these welders will be allowed to weld the pipe joints. The S.O. shall be at liberty to withdraw his approval to any welder responsible for making joints which fail to meet the required standard.


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6.4 Making Joints with Mechanical Couplings and Flange Adaptors Mechanical couplings and flange adaptors joints shall be installed in strict

accordance with the instructions given by the manufacturer and to the S.O.'s approval.

Before jointing, the ends of each pipe shall be free of any debris and any

protuberances which may have been caused by rubbing of the packing material and also be removed all rust at exposed places due to stripping of the bitumastic coating. The ends shall then be recoated with a quick drying solution of bitumen so as to produce a smooth coat of uniform thickness.

On completion of the joint the surfaces of the coupling and adapter shall be

painted with a quick drying primer and an external sheathing mould formed to enclose the coupling and ends of the adjoining pipes. This work shall be carried out by specially competent and skilled men in strict accordance with the instructions given by the manufacturer.

The primer and sheathing material compatible to the sheathing material on

the pipes and the mould boxes and funnels required to form the protective mould and whiting used for lining the mould boxes prior to each pour shall be supplied by the Contractor, who shall also supply the necessary boilers to heat the sheathing material to the application temperature. The Contract Rates for making coupling and adapter joints shall cover all costs in complying fully with the requirements of this Clause.

Mechanical couplings and flange adapters located in chambers shall be

painted with two coats of bituminous paint. 6.5 Making Flanged Joints When making flanged joints care shall be taken to see that the rings remain in

position undistorted while the bolts are tightened and the ring may be fastened to the bolts with cotton thread, or stuck to the flange with rubber solution. The use of jointing paste will not be permitted. The bolts shall be tightened in regular sequence starting from opposite sides of the bolt circle and then going round in this way until every bolt is tight. Excessive tightening of flanged joints shall be avoided. For precise tightening, preset torque wrench shall be used.

All MS flanges shall be protected with minimum 200 microns thick fusion

bonded epoxy coating. The exposed part and welds and the flanges on MS pipes shall be painted with two coats of epoxy paint for flange located in chambers.

The exposed metal and welds on flanges on MS pipes which will be

subsequently buried in trench and not encased in concrete shall be carefully wrapped with Denso' tape according to manufacturer's recommendation.

For PE pipe systems, the MS flanges and bare metal on MS pipes shall be

protected by anticorrosion paint as specified but no petroleum or bituminous based paint shall come into contact with PE stub ends.

The Contract Rates for making flanged joints shall cover all costs in complying fully with the requirements of this Clause.


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6.6 Measurement of Ductile Iron, Cast Iron, Steel, PE Pipes and Fittings Spigot and socket ended MS and Ductile Iron and PE straight pipes shall be

measured in linear metre, their lengths being defined as their effective lengths as laid measured along the centre line of the pipe. The effective length shall mean the net length of the pipe as laid, after deduction of the length of overlap at any spigot and socket joint to be made with the pipe.

Joints, pipe specials, valves and fittings shall be measured separately and by

number. The Contract Rates for laying steel pipes, Ductile Iron, PE pipes and specials

shall include for the full cost of storage at Site, hauling and handling, repairing lining and sheathing, replacing damaged pipes where necessary and laying in position in the Works ready for jointing and/or building in together with other costs incurred in complying with the requirements of the Specification for which no separate items are included in the Bill of Quantities.

6.7 Concrete Protection to Pipes Pipes shall be bedded and haunched or fully surrounded in concrete where

shown on the Drawings or as directed by the S.O.. Where concreting is required a sufficient amount is to be placed and left to set in position before the joints are made to prevent any subsequent movement of the pipes when further concrete is placed.

In order to allow relative movement between pipes, flexible joints shall not in

general be partially or completely cased with concrete. Concrete bedding and haunching or surround shall be omitted for a distance of 150 mm from the face of flexible joints except as may be otherwise directed by the S.O..

In general pipes shall be bedded on or protected by concrete in the following

circumstances:- (i) A 150 mm bed and partial haunch where the pipe is in rock. (ii) A 150 mm surround where the pipeline is under streams and ditches. 6.8 Thrust and Anchor Blocks Bends, tapers, tees and other points where horizontal thrust will occur shall

be supported with concrete blocks. The cover between the side of the pipe and the excavated face of the ground which will subsequently take the thrust shall in no circumstances be less than 150 mm. Flanges and flexible joints should not be cast in the concrete blocks.

Where pipes are laid at gradient steeper than 1 in 12 anchor blocks in

concrete shall be provided at the middle of pipes as follows: -


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Gradient Exceeding Anchor Blocks

1 in 12 1 in 8 1 in 3

Every third pipe Every second pipe Every pipe

Details of thrust and anchor blocks are given on the Drawings. The

dimensions shown may, however, be amended by the S.O. after examination of the ground prior to concreting, having regard to the likely thrust developed under test pressure and the actual nature of the ground. Additional anchor blocks may also be needed.

For horizontal bends in cross-fall ground, care shall be taken to ensure that

additional cover over the pipes is allowed in order that the same passive resistance may be developed as would be the case in level ground.

For thrust and anchor blocks to fulfill their purpose they must abut against

undisturbed ground. Where timbering has been used in the excavation it shall be withdrawn as the concrete is being placed.

6.9 Valve Chambers Valve chambers shall be constructed in accordance with the details shown on

the Drawings or as directed by the S.O.. The same care shall be taken as for thrust blocks to ensure that concrete transmitting thrust abuts against undisturbed ground.

The Contractor shall first obtain from the S.O. the exact requirements relating

to the construction of each chamber. Drainage from valve chambers to suitable outfalls shall be provided as

directed by the S.O. 6.10 Crossing Over Streams, Culvert and Rivers Typical details of pipework and support arrangements of over-crossings at

streams and rivers are shown on the Drawings. The Drawings shows pipe specials which are required for each crossing. The lines, and levels of the pipework shall be as shown on the Drawings or as directed by the S.O. on site.

6.11 Payment for Pressure Testing Pipelines and Specials The cost for testing pipelines and specials shall include for the supply of clean

water and all necessary testing apparatus, pumps, pressure gauges, flowmeters and pipework, the cost of supervision and labour in testing and re-testing, if necessary and all other work, materials and equipment in complying with the requirements of Clause 1.13.


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6.12 Sterilising and Flushing Pipelines When the final connections have been made and the pipelines have been

tested to the satisfaction of the S.O. the pipelines shall be again jointly inspected that they are cleaned before they are thoroughly sterilised and flushed by the Contractor. Water for sterilisation and flushing shall be obtained by the Contractor at his cost with a formal application and approval from SAJH. All necessary equipment (inclusive of approved flow meter) for the transfer of water is deemed to be included in the Contract Rates.

The operation of all valves including scour and air valves shall be checked and

inspected jointly by the Contractor and S.O. and any necessary adjustments made to ensure correct operation.

The section of the treated water main to be sterilised shall be filled with water

mixed with a solution of chloride of lime containing about 20 milligrams per litre of chlorine. The Contractor shall have to adopt a dosing system to sterilise the lines effectively. The system shall be provided with a set up of temporary equipment, chemical mixing tank mixer, dosing pump and other necessary accessories for the solution to be injected into the lines when treated water will be introduced gradually. After the main has been filled with chlorinated water, it shall be closed and left for a minimum of 24 hours. The main shall be deemed to have been sterilised if the samples of water taken from various tappings on the main show minimum chlorine residual of 0.2 ppm.

After the main has been sterilised to the satisfaction of the S.O. it shall be

flushed with clean water. Consumer connections shall not be connected and commissioned before the pipelines has been sterilised and flushed to the satisfaction of the S.O.

6.13 Payment for Sterilising and Flushing Pipelines The rate for flushing and/or sterilising the pipeline shall include for the full

cost of supplying and pumping water, supplying, mixing and dosing chemicals, the cost of all apparatus, the cost of supervision and labour and all other work, materials and equipment in complying with the requirements of Clause 6.12.

6.14 Payment for Road Restoration Items in the Bill of Quantities for restoration of metalled roads except where

expressly stated otherwise shall apply to road reinstatement. The charges if any imposed by the Authorities for work carried out on metalled roads shall be deemed to be included in the relevant items in the Bill of Quantities.

Where the restoration is to be carried out by the Contractor, measurement

shall be in accordance to the Bill of Quantities provided. Where the restoration is to be carried out by the Authorities, the Contractor

shall comply fully with all regulations and requirements as stipulated by the Authority and such restoration shall be deemed to have been restored by the Contractor. The Contractor shall be paid in accordance to the appropriate


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rates in the Bill of Quantities. Temporary reinstatement prior to final restoration shall be measured separately in addition to permanent restoration.

6.15 Clearing Up During the progress of pipelaying work the Contractor shall clear up the Site

and remove from the surface of the ground all temporary buildings, plant, materials, litter, rubbish and surplus spoil which may have been left on the ground or in and about the Works or lands temporarily occupied by the Contractor and he shall leave in a clean and slightly condition all and any lands occupied by him. Clearing up of the Site as herein specified shall follow closely on the refilling of the trench.

6.16 Indicator Posts The Contractor shall provide and fix precast concrete indicator posts, details

of which are shown on the Drawings on the centreline of the pipes at bends, valves, washout, air valves and other points as directed by the S.O. Name and number plates fabricated from 16 gauge aluminium sheets with embossed lettering shall be fixed to the post with stainless steel screw and fibre glass washers.

The post shall be set in concrete firmly into the ground to the depths shown

on the Drawings and the backfilling well rammed in and around. Indicator post shall be measured by number. The rate for the supplying and

fixing complete the posts shall include for all necessary concrete, excavation and backfilling.

6.17 Painting Pipework and Valves in Chambers After installation the exposed surfaces of all pipework, valves and fittings in

chambers shall be properly cleaned, primed and painted thoroughly with approved paint.

The paint required for these purposes shall be supplied by the Contractor and

approved by the S.O. The cost of supplying primer and paint and painting pipework and valves shall be included in the rates for laying pipes and the installation of valves.

6.18 Painting Pipework Above Ground Steel pipework for installation above ground including stream and river

overcrossings shall be painted with two pack polyamide cured epoxy zinc phosphate primer of minimum 75 microns dry film thickness at the place of manufacture. After installation, damaged areas and welded areas shall be power brush cleaned and painted with the same primer of same thickness. Then the whole of the exposed pipe shall be painted with 100 microns dry film thickness of two-pack high build amine-adduct cured epoxy paint followed by 50 microns dry film thickness of two-pack aliphatic polyurethane finish paint. Brand and colour of paints are to the approval of the S.O.


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6.19 Disposal of Surplus Goods On completion of the Works the Contractor shall deliver to the SAJH’s store

as directed by the S.O. all materials and plant provided by SAJH and taken over by the Contractor but which have not been used in the Works. These shall be placed and arranged, and if necessary protected, as directed by the S.O.

6.20 Payment of Fees to Authorities The Contractor shall pay to all authorities all deposits, fees and charges

required to be paid in relation to the execution of the Works or to any Temporary Works.

If after due notice to the Contractor calling his attention to the necessity for

the payment of fees and/or charges to the Authorities the Contractor has failed to make payment, Employer shall be entitled to pay such fees and/or charges direct to the Authorities concerned out of any moneys at any time due to the Contractor under the Contract and such payment shall be deemed to be payment made to the Contractor under and by virtue of the Contract.

The cost of all fees and charges payable by the Contractor shall be deemed to

be included in the Contract Rates unless otherwise expressly provided for in the Bill of Quantities.


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SECTION 7.0 – PIPE JACKING



7.0 PIPE JACKING 7.1 General Pipe jacking shall be the process of installing precast reinforced concrete pipes

below a surface obstruction by driving them successively through the in-situ soil from one pit (driving pit) to another (the receiving pit) such that the finished pipe forms a watertight continuous conduit between the pits on the desired alignment for the laying of MS pipeline.

Plans and details of the equipment, materials and the method of construction

to perform and complete the work shall be submitted by the Contractor and must be approved by the S.O. before commencing these operations. Approval by the S.O. shall not relieve the Contractor of his sole responsibility for the efficacy, reliability and soundness of the method employed in completing the work in a satisfactory manner.

The Contractor shall satisfy himself as to the soil conditions along the pipe

jacking route and if he judges it to be necessary, he shall carry out further soil investigations at his own cost.

It shall be the responsibility of the Contractor to maintain stable soil

conditions at the jacking face to prevent loss of ground above the jacking operation and movement of the surrounding earth. The methods of maintaining face stability and preventing ground movement and subsidence shall be by means of compressed air or other plenum methods where fluid slurry or earth pressure is applied to the tunnel face. Alternatively, unstable ground ahead of the jacking face may be stabilised by the injection of suitable chemicals. Methods which require dewatering of the ground will not be accepted, nor will methods which may lead to significant ground loss. The Contractor's proposal must be submitted to the S.O. for his approval.

Movement or settlement of structures, utilities and pavement shall be

monitored by the Contractor during the jacking operation and reported to the S.O.. If movement or settlement occurs which in the opinion of the S.O. may cause damage, the Contractor shall take immediate action to prevent further movement, settlement or damage. He shall repair at his own cost any damage and restore structures or pavements to the satisfaction of the S.O.

The Contractor shall be responsible for inspecting the location and

familiarising himself with the conditions under which the work will be performed and with all necessary details as to the orderly execution of the work. The omission of any details shall not relieve the Contractor of full responsibility for the satisfactory installation of the work in its entirety. No monetary or other claims made by the Contractor on the grounds of want of knowledge will be entertained.

7.2 Tender Submission The tenderer shall submit with his tender the following particulars relevant to

his design and proposal for pipe jacking :-


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(I) Four (4) copies of a detailed specification giving full particulars of the jacking pipe, pipe joint and construction method proposed.

(II) Four (4) sets of calculations of his design and proposal.

(III) Four (4) sets of drawings showing in sufficient detail his design and

proposal. The tenderer's design and proposal shall be based on the general

arrangements shown on the tender drawings which accompany the tender document as far as possible to suit the tenderer's proposed system.

7.3 Surface Reinstatement in Road Verges, Fields, etc. Where excavation is in road verges, fields and grassed areas, the turf

previously removed will suffice for surface reinstatement providing that the grass has not been killed during stacking and that the surface is free from all loose stones.

After refilling excavation as specified, the Contractor shall replace all topsoil

previously removed and it shall be evenly distributed and levelled over the full extent of the stripped area. The working space occupied by the Contractor which was originally covered with grass if destroyed during the course of construction shall be covered with 50mm of topsoil, close turfed and maintained until the new grass is properly established at the Contractor’s expense. Other areas not originally covered with grass shall be restored to their former state.

Road verges shall be restored to their original width and to a minimum fall of

1 in 24 away from the road and towards the ditch (if any). Restoration of the dip shall be carried out unless the fact that no dip existed prior to pipelaying has been recorded in writing and agreed to by the S.O.

The Contractor shall restore all surfaces in a condition not inferior to that

which existed prior to commencement of works. Any damage to the metalled road due to pipejacking work alongside road

verges or shoulders shall be reinstated to the satisfaction of the authority concerned at no extra cost to Employer.

For the purpose of determining the required extent of reinstatements

described above, the Contractor shall jointly with the S.O. make assessment of the existing Conditions at each work site before the work commences. The Contractor shall produce two sets of photographs and other records of the existing situation on site and they shall be jointly signed. One set shall be kept by the Contractor and one set shall be submitted to the S.O.


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7.4 Prospecting The Contractor shall prospect for the position of buried or otherwise hidden

obstructions such as existing services, drains, pipes, cables, culverts, etc. Trial holes and exploration trenches to ascertain the exact positions of these shall be sunk, well ahead of pipejacking and excavation, in places where they are known or thought to be and elsewhere and these shall be backfilled with approved materials immediately and in any case not exceeding 24 hours and subsequently reinstated. Approved marker posts shall be erected to mark the position of all located services, drains, etc. and these shall not be removed until reinstatements has been completed. The S.O. shall instruct further prospecting if he is not satisfied with the sufficiency of the Contractor’s prospecting.

Where necessary the Contractor shall make arrangements prior to excavation

of jacking and receiving pits and pipejacking proper for the temporary or permanent support or diversion of services, rains, etc. to the approval of the S.O. and the authority concerned. The full cost of prospecting shall be deemed to be included in the relevant Contract Rates.

Attention is drawn to clauses concerning the responsibility of the Contractor

for the security of existing services. The Contractor shall be deemed to have allowed for the unavoidable delay of

the Works due to any obstruction he may encounter with the existing services and no claim for any extra costs on account of this will be allowed.

7.5 Performance Requirements The centre-line of the fully jacked pipes forming a continuous sleeve shall at

all points along its length be within 75mm of the required alignment in the horizontal plane and 25mm in the vertical plane.

No movement, upheaval or settlement of soil which in the opinion of the S.O.

may cause damage to structures, utilities or pavements shall be permitted. The pipeline laid in the jacked pipe sleeves shall pass the watertightness test

specified for the pipelines in trench. 7.6 Approval of Owner Before commencing preparations for pipe jacking the Contractor shall obtain

the written consent to his proposed procedures of the Owner or Owners of the land, services and structures below which (or close to which) the jacked pipeline will pass. Unless otherwise stated, all costs, expenses, charges, rental, compensation etc., imposed by the Owner shall be deemed to be included in the Contract Rates.


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7.7 Jacking Operation The Contractor shall be fully responsible for the materials, equipment and

facilities required in conjunction with jacking the pipes. Before starting work, the Contractor shall submit to the S.O. for approval, a

detailed schedule of the entire jacking operation. Approval of such schedule shall not relieve the Contractor of his responsibility to provide a fully satisfactory installation. The Contractor shall include with his submission evidence that he has successfully completed a jacking installation using procedures similar to those proposed.

Where chemical stabilisation of soil is used, a chemical grout shall be pressure

injected into the soil over and ahead of the pipe jacking to stabilise the soil. The chemical grout used shall have a demonstrated history of success for stabilising soils similar to that through which the pipe is to be jacked.

Where a mechanical shield is used, the Contractor must provide proof that the

particular model of shield has been used successfully in soils similar to that on the site. The crew for the operation of the shield must be specialist, with experience in the use of that particular type of machine.

After the jacking operations has begun, the Contractor shall work

continuously and expeditiously in accordance to programme until the complete length of jacked pipes is installed. This continuous work where required shall not be construed as overtime work.

During jacking and excavation, the Contractor shall constantly ensure that the internal lining of the jacking pipes is not damaged, and he shall remove the excavated spoil to the jacking pit by conveyor to minimise traffic on the invert.

The pipes shall be jacked into place true to line and level. The maximum

tolerance allowable in the displacement of the centreline of the jacked pipe from the design centreline is 75mm in the horizontal plane and 25mm in the vertical plane but there shall be no backfall at any point.

The pipes for the jacking operation shall not exceed 4m long. The pipe ends

shall be jointed by MS thrust collars/sleeves before the pipeline is jacked. Details of how the pipes are to be lowered into the pit and jointed shall be

submitted to the S.O. for approval. The Contractor shall be required to furnish and install and remove to the

extent required, thrust blocks or whatever provisions that may be required for backing up the jacks employed in jacking the pipe forward. The jacking pit shall also be equipped with steel rails or beams embedded in concrete for placement and alignment of each pipe during the jacking operation. Other method may be used subject to the approval of the S.O..

The Contractor shall be fully responsible for the design and construction of

the jacking and receiving pits, thrusting wall, installation of jacking equipment, sheeting, bracing, etc., and for the efficient execution of the


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jacking operation. Full details of the proposals, including plant, shield machine, equipment, operating procedures, jacking pit and intermediate jacking stations etc., shall be submitted to the S.O. and shall be fully satisfactory to him before construction. However, review of the plans shall not relieve the Contractor from his responsibility to provide a safe and satisfactory jacking pit. On successful completion of the jacking operation, jointing of the length of jacked pipes, jointing and installing of the MS pipeline, hydraulic pressure testing of the pipelines and after the connections at the extreme ends of the MS pipeline have been made, the Contractor shall pressure grout the jacked pipes to fill all the voids existing outside the pipe. Grouting shall be undertaken through holes as specified herein. Then, the Contractor shall remove complete the jacking pits and receiving pits together with all the temporary works. He shall also backfill the pits with well compacted suitable approved materials.

The Contractor shall be required to monitor closely the progress of the jacking

operation. Daily site records of thrusting pressures, rate of thrusting, the line and level measurements of the jacking pipes and any movement or settlement of existing structures shall be properly maintained and shall be submitted to the S.O..

For the sections of the pipeline crossing under roads, railway or structures

along the pipeline route, the Contractor shall be required to incorporate in his tunnelling method measures to arrest settlement or upheaval of the soil so as to safeguard the integrity of the structures and other property. The Contractor shall ensure that the traffic flows along railway lines and roads are not affected in any way by his work.

7.8 Safety The minimum of plant shall be used in the pits, and any which produces

noxious gases or is operated by electricity at a greater voltage than 240V shall be permanently outside the pit at ground level.

A ladder shall be fixed permanently in the receiving pit. Two ladders shall be

permanently fixed on opposite sides of the driving pit, one on each side of the pipe jacking line. These ladders shall be kept clear of obstructions to allow rapid exit in an emergency. Excavated materials and plant other than small tools shall not be passed via the ladder but shall be handled by crane.

Pits shall be securely fenced to prevent unauthorised persons from entering

in. All persons entering the pits shall wear safety helmets constantly, and shall

leave the pits for meal breaks, rests and the like. At the beginning of each shift and after any break for refreshment or other

reason, the Contractor shall provide and use an approved instrument to check for noxious gases before anyone re-enters either pit.

All costs associated with the provision of safety equipment and measures shall

be deemed included in the Contract Rates.


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7.9 Design of the Jacking Pipes The Contractor shall design the pipes to be jacked and the pipe joints in

accordance with the jacking procedure and operation proposed by the Contractor. The design shall be submitted with full detailed calculations to the S.O. for approval before construction commences. The details of the jacking pipes are shown on the Drawings and the design shall take into account the following requirements: -

(1) The pipes for jacking operation shall be precast concrete pipes

manufactured by centrifugal or other equivalent process to be approved by the S.O.

(2) All pipes shall be manufactured with two sets of grout holes. Each set

shall consist of three grout holes spaced at 120 degrees on centres circumferentially located at quarter points from either end of the pipe.

(3) The length of each pipe shall not exceed 4m and the pipe ends shall

have an external rebate suitable to accommodate a MS joint/thrust collar. The collar shall be designed to take the jacking load applied and transfer the load to the next pipe.

(4) The thrust collar shall be fitted onto the pipes with rubber rings to

prevent the ingress of water into the pipe from outside. (5) The precast reinforced concrete pipes shall be sufficiently reinforced

with steel to withstand all stresses induced by handling, jacking, earth and water pressure and all working loads at the depth at which they are to be used without cracking, spalling or distortion. The pipes shall be of at least strength Class ‘2Z’. A load factor of not larger than 1.5 times shall be used in the calculations to determine the strength of the pipes required. The strength of the pipes shall be tested by the three edge bearing test. When subject to the design load in such a test, the maximum crack width developed on the pipe shall not exceed 0.25mm. All such tests shall be carried out at the expense of the Contractor.

(6) The Contractor shall submit full details of his proposal for the pipes

giving detailed drawings showing sizes, reinforcement and joint details, calculations, name and address of proposed manufacturer and the manufacturing processes to the S.O. for approval. The proposal shall be endorsed by a Professional S.O.

The jacked pipes shall be designed to withstand, in conjunction with the jacking load applied, the following external loads: -

(i) Highway loading of 45 units of Type HB loading in accordance with BS

5400, for pipe jacking under JKR roads. (ii) Overburden load as shown on the Drawings.

The nominal diameter of the jacking pipe shall be as shown in the Drawings

for laying of the specified pipe.


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7.10 Laying and Connections of Pipeline in Jacked Reinforced Concrete Pipes Sleeve

The laying of the MS pipeline shall only commence after the full completion of

the jacking of the reinforced concrete pipes to the approval of the S.O.. The MS pipes shall be in length of 4 metres or less and to be jointed by welded split collars as specified in Clause 2.14. of this Contract. In addition all welded joints shall be tested by ultrasonic examination in accordance with BS 3923 in the presence of the S.O. or his representatives. The S.O.'s instructions given as a result of the examination of ultrasonic results shall be final. The Contractor shall submit his proposals to the S.O. for site ultrasonic examination. The size, number and make of ultrasonic equipment proposed shall be stated. The Contractor shall provide adequate equipment and qualified and experienced personnel to conduct the ultrasonic examination.

The S.O. reserves the right to carry out any independent ultrasonic

examination of the welded joints as he may deem fit. Such independent ultrasonic examination shall be carried out by an Inspector appointed by S.O. and paid through items in the Bill of Quantities. The Contractor shall provide such assistance, labour, materials, electricity, supply ultrasonic examination equipment and other apparatus as may necessary to allow a thorough and extensive independent examination to be carried out.

After each section is jointed by welding and approved by the S.O. or his

representatives, the MS pipe shall be jacked or pushed through the sleeve. The bottom of the MS pipes shall be suitably supported on rollers or other means to prevent scouring of the MS pipe external surfaces. Care shall be taken to ensure that the internal concrete linings are not damaged during the operation. The pipe ends shall be properly braced to prevent damage. The end of the jacked reinforced pipe sleeve shall be grouted after the full length of MS pipe has been jacked/pushed through.

Connections at the extreme ends of the MS pipeline shall be made only upon

successful completion of the hydraulic pressure test of the pipeline as specified in Clause 2.17. of this Contract.

The connections at the two ends of the jacked pipeline will be made at the

jacking or receiving pits. The Contractor shall maintain and keep these pits intact and in a safe condition to facilitate the connections. The Contractor shall remove all other temporary works and any concrete blocks including cutting and removing part of the walls of the pits that are in the way of the pipework connections.

When the Contractor has completed the connections of the pipelines and has

completed the protection of these connections with sand or concrete surround, he shall then backfill the pits with well compacted suitable approved materials. The removal of the temporary bracings and struttings shall be carried out systematically together with the backfilling of the pits to prevent collapse of the pit walls. The walls of the pits shall only be removed when the backfill of the pits are completed.


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7.11 Alternative Method of Pipe Jacking Methods of pipe jacking other than described above may be proposed by the

Contractor and subject to the approval of the S.O.


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SECTION 8.0 – EARTHWORKS



8.0 EARTHWORKS 8.1 Definitions

The following terms shall have the meanings hereby assigned to them :-

(i) Topsoil : means any surface material, including turf, suitable for use in soiling areas to be grassed or cultivated.

(ii) Rock : means material which in the opinion of the S.O. would normally have to be loosened either by blasting or by the use of pneumatic tools (excluding clay spades worked on an air compressor) or by other rock quarrying methods or, if excavated by hand, by the use of wedge and sledge hammers. An isolated solid boulder or detached piece of rock shall qualify as Rock only if it exceeds 0.15 cubic metre in volume.

(iii) Bulk Excavation

: means excavation in open cut (excluding Trench excavation and Incidental Excavation) down to levels specified on the Drawings or otherwise as being the general levels after completion of excavation.

(iv) Trench Excavation

: means excavation of trenches into which pipes or cables are to be laid to levels and limits specified on the Drawings or otherwise directed by the S.O.

(v) Incidental Excavation

: means excavation below or outside the limits of Bulk Excavation and Trench Excavation.

(vi) Excess Excavation

: means excavation outside the limits specified or shown on the Drawings or directed by the S.O. for Bulk, Trench or Incidental Excavation.

All reference to "excavation" or "excavations" shall apply to Bulk, Trench, Incidental and Excess Excavation(s) except where clearly stated to the contrary.

8.2 Levels to be Recorded

Before the surface of any part of the Site is disturbed or the works thereon are begun the Contractor shall take and record levels of any such part, in the manner specified or as agreed with the S.O. in his presence and such levels when agreed with him shall form the basis for measurement.

8.3 Explosives and Blasting

The S.O. shall have power to regulate, restrict or prohibit blasting if in his opinion it is necessary to do so for the safety of persons or property or to safeguard the Works. No blasting shall be carried out in any part of the Works without the permission in writing of the S.O. Such permission shall not absolve the Contractor from any of his obligations or liabilities under the


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Contract and he shall take all necessary precautions including the use of blasting nets to avoid damage, loss or injury to persons and to public or private property.

The Contractor shall keep the S.O. fully informed at all times when blasting is proposed to be carried out and of any details that may be required concerning strength of charges and their positions.

Explosives shall not be used within 15 metre, or such greater or lesser distances as the S.O. may direct, of concrete placed in the Works, of any existing structure, water main, electric cable, sewer or other services. Notwithstanding the above, due to the close vicinity of the existing reservoir, all excavations into rock by blasting to prepare foundations for any proposed reservoir next to existing reservoir shall be carried out with extreme care. Before any rock blasting commences, the Contractor shall submit to the S.O. a detailed controlled blasting plan.

The purpose of the control of blasting operations is to eliminate any possibilities of damage to the existing reservoir, pipelines and structures.

Approval of the Contractor's proposal shall not absolve him from responsibilities in the event that the existing structures are damaged as a result of the blasting method used.

All details regarding the type of explosives or chemicals, strength, spacings, depths, positions of charges, detonation delays used and the method of monitoring the magnitude of vibration generated shall be supplied to the S.O.

Pilot tests to assess the effectiveness of the controlled blasting shall be conducted at an approved location within the site before the method is approved. The Contractor shall provide vibration measuring instruments to monitor the magnitude of vibration caused by the proposed arrangements with respect to explosive charges, spacings, detonation delays, etc. The instrument shall be able to measure resultant peak particle velocities from measurement in X, Y and Z planes and record measurements digitally. Sensors shall be mounted at different positions on the existing structures as instructed by the S.O. The instrument shall be a triaxial vibration recorder or similar and shall be capable of measuring velocities in the range of 50-70 mm/sec. The cost of providing such vibration measuring instrument shall be deemed to be included in the rates for rock excavation in the Bill of Quantities.

The Contractor shall obtain the necessary permits and licences for the use, storage, transport and handling of explosives and shall provide a store or stores suitable for explosives in accordance with local regulations.

8.4 Disposal of Materials

All requirements herein for the disposal by the Contractor of materials arising from site clearance or from excavations are subject to the provisions of the Specification.


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8.5 Excess Excavation to be made good

The Contractor shall at his own expense be required to fill the Excess Excavation with such kind of suitable fill material or in such class of concrete as may be reasonably required by the S.O. having regard to the circumstances.

Any surplus unused or unsuitable material resulting from Excess Excavation shall be removed from the Site by the Contractor at his own expense.

8.6 Site Clearance

All areas of the Site marked on the Drawings or specified for clearance or from which material is to be excavated or upon which filling is to be deposited shall be cleared to the extent required by the S.O. of all buildings, walls, gates, fences and other structures and obstructions and of all bushes, hedges, trees, stumps, roots and other vegetation except for trees marked for preservation. Material so cleared shall be disposed off the sites to dumpsites approved by the local authority or as may be reasonably directed by the S.O. Open burning of cleared materials is strictly prohibited.

8.7 Trees

Trees shall be uprooted or cut down as near to ground level as possible. Branches and foliage shall be removed and burnt to ash or disposed of off the Site. Useful timber within Reserved Land of the Government or Authorities shall remain the property of the Government and shall be cut into suitable length and stacked properly.

8.8 Stumps

Stumps and roots whether existing or remaining after tree felling shall where directed by the S.O. be grubbed up and disposed of off the Site. The resulting hole shall be filled with approved material and properly compacted to the same dry density as the adjoining soil.

8.9 Measurement of Site Clearance

Items in the Bill of Quantities for site clearance shall include for clearing the Site all as specified including all fallen trees and their stumps. Site clearance shall be measured as the area so cleared on plan to the S.O.'s requirements and instructions.

8.10 Stripping Topsoil

Where ordered by the S.O. topsoil shall be stripped, to such depths and over such areas as he may direct, as a separate operation prior to any further excavation which may be required.


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8.11 General Excavation

General excavation means excavation, whether Bulk or Incidental, required for structures and shall not include Trench Excavation.

The ground shall be excavated by such methods and to such dimensions and depths as shall allow for the proper construction of the Works.

Where nominal 'payment' limits of excavation are not shown on the Drawings or otherwise specified they shall be deemed to be the minimum net limits which would allow the outline of the completed structure to be lowered vertically from ground level into its final position. The Contractor shall make his own allowance for any working space required, and any excavation outside the aforesaid limits which has not been ordered by the S.O. whether it be excavated to suit the Contractor's method of working or unavoidable overbreak or due to his carelessness or error, shall be held to be Excess Excavation.

8.12 Trench Excavation

The line and level of trenches shall be as shown on the Drawings or as directed by the S.O. Before commencing Trench Excavation, the route of the trench shall be pegged out accurately and the existing ground levels shall be agreed with the S.O. Strong sight rails shall then be fixed and maintained at each change of gradient, and at as many intermediate points as may be necessary. On these rails shall be marked the centre line and the level to which the excavation is to be carried out, such rails being not more than 35 metre apart. Trench Excavation shall be carried out by such methods and to such lines dimensions and depths as shall allow for the proper construction of the Works, provided always that, unless the S.O. permits otherwise and subject to any specific requirements of the Specification no Trench Excavation shall be less than the widths stated below :-

D Clear Width of Trench

for Backfill With Excavated Material

Clear Width of Trench for Trench for Backfill

With Sand MS/DI

Pipes

PE Pipes MS/DI Pipes

PE Pipes

Communication pipes up to 63mm OD

NA - NA 300mm

Not exceeding 500mm

D + 450mm - D + 450mm

D+300mm

Exceeding 500mm but not exceeding 750mm

D + 600mm - D + 600 mm

-

Where D in mm is the external diameter of the MS and DI pipe including any sheathing. Where D in mm is the nominal external diameter of the PE pipes.


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Notwithstanding the foregoing, any rock in trench excavation shall be so excavated that the clearance between the pipe when laid and the rock sides and bottom of the trench is kept to the minimum limits necessary to provide for the specified thickness of bedding haunching and surround to the pipe. Any excavations outside these limits whether for working space or due to overbreak shall be held to be Excess Excavation. The sides of Trench Excavation shall be vertical as far as possible. However, the Contractor shall be responsible to take the necessary precaution and safety measure to ensure such Trench Excavation is safe for working. Stones shall be removed from the trench invert and holes so formed shall be filled with well compacted selected soft material. Where mechanical excavators are used, the last 150 mm of the excavation shall be removed with care to the required depth, and the trench invert carefully trimmed true to level. Any widening or deepening of Trench Excavations necessary to accommodate curves, joints or bends in the pipe or to provide extra working space for the construction thereof shall be held to be Excess Excavation. Trench Excavation shall wherever practicable be carried out in such a way that every part of the excavation is at least 600 mm clear of the existing edge of the carriageway. In any event the Contractor shall take special precautions, which shall include the continuous support of the sides of the excavation, from the time when excavation is begun until the refilling of the trench is placed, to ensure that there is no disturbance of the adjacent road or road foundation. For the purpose of measuring certain work in connection with Trench Excavation "nominal limits" of Trench Excavation are stated above and any excavation outside these limits, which have not been ordered by the S.O. shall be held to be Excess Excavation.

8.13 Trench Excavation in Roads, Road Shoulders and Footpaths

All Trench Excavation and other work carried out within the limits of any road reserve shall be completed as rapidly as possible and not more than half of the width of the carriageway shall be obstructed at one time unless a full diversion has been provided and approved by the Authorities. A minimum width of 4 m wide of traffic lanes shall have to be kept clear for flow of traffic and where necessary the shoulder should be strengthened to the satisfaction of relevant Authorities at the Contractor's own cost. Road drains and grids shall be kept free from obstruction. Where trenches are excavated in public roads, road shoulders and footpaths of congested areas necessitating carting spoil to distant tips, the Contractor shall employ suitable plant to ensure that the passage of traffic past the Works is not impeded by the loading and unloading of spoil. Excavated materials shall not be left standing on road pavement. All trenches on metalled roads shall not be left open for more than one day and all trenches on road verges shall not be left open for more than three days. Tarmacadam and similar road surfaces shall be broken out neatly along the trench line using a diamond disc road cutter to keep the edges straight and vertical.


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The Contractor shall take special precautions, including the continuous support of the sides of the excavation from the time excavation is begun until refilling of the trench is completed to ensure that there is no disturbance of the adjacent road or road foundation. The Contractor shall also provide barricades to fence off the works and approved road sign boards placing at regular intervals to ensure safety of the public and vehicles.

8.14 Trench Excavation in Fields, etc.

The term "fields" includes fields, plantations, padi, grass verges and the like. The Contractor shall have particular regard to the safety of livestock in fields or which may be introduced to the fields, and shall ensure that all excavations, access routes and steep or loose slopes arising from the Contractor's operations in these fields are adequately protected.

8.15 Rock and other Materials in Excavations

Any material in the excavations which the Contractor considers may be classified as Rock as defined in Clause 8.1 shall be notified to the S.O. before excavation of the material is begun. The quantities of Rock or material alleged to be Rock excavated from within the nominal limits of excavation shall be recorded by the S.O. and the Contractor each day or at such shorter intervals as the S.O. may require. Only such proportion of material so notified, recorded and signed shall qualify for additional payment as Rock. Overbreak (that is excavation outside the nominal limits of excavation) shall be kept to a minimum and shall be held to be Excess Excavation. Materials like shale and weathered sandstone strata may not be classified as 'Rock' within the meaning of Clause 8.1. These materials are tough and may exceed conventional methods of excavation. Bulk excavation of these materials shall include the use of an efficient parallelogram type ripper having a single shank in sound working condition for attachment to a track machine also in sound working conditions with a minimum weight of 24 tonnes and a nett power rating of not less than 240 hp. These materials shall only be classified as 'Rock' when, in the opinion of the S.O., they cannot be ripped efficiently as described above.

8.16 Supporting Excavation

The Contractor shall well and effectively support the sides and ends of all excavations to prevent any fall or run from any portion of the ground outside the excavation and to prevent settlement or damage to structures adjacent to the excavation. Any extra excavation necessary to provide space for such support or other working space shall be held to be Excess Excavation. If, for any reason, any portion of the bottoms, sides or ends of any excavations shall give way the Contractor shall at his own expense take all necessary remedial measures including the excavation and removal of all the ground thereby disturbed both within and without the nominal limits of excavation and such extra excavation shall be held to be Excess Excavation. Where the Contractor elects and is permitted by the S.O. to perform excavations with sloping faces (other than sloping excavations shown on the Drawings or required as permanent features of the Works) and without


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shoring, the excavated faces shall be to stable slopes and heights and the resulting extra excavation shall be held to be Excess Excavation.

8.17 Trimming Excavations

When excavating to specified levels for the foundation of any structure or pipes or to specified limits for the faces of any structure required to abut against undisturbed ground the Contractor shall not excavate the last 150 mm until immediately before commencing the constructional work, except where the S.O. shall permit otherwise. Should the Contractor have excavated to within 150 mm above these specified levels or to within 150 mm of these specified limits before he is ready or able to commence the constructional work he shall, where required by the S.O., excavate further so as to remove not less than 150 mm of material immediately before commencing the constructional work and such further excavation shall be held to be Excess Excavation. Before commencement of any constructional work all shattered and loose material shall be removed from the excavations by hand so as to ensure that the work rests on a solid and perfectly clean foundation or abuts against solid ground.

8.18 Inspection of Excavation

When the specified levels or limits of excavation are reached the S.O. will inspect the ground exposed, and if he considers that any part of the ground is by its nature unsuitable he may direct the Contractor to excavate further. Such further excavation shall be refilled to the specified levels or limits with concrete, selected excavated materials or selected imported material as directed by the S.O. but shall not be held to be Excess Excavation. Should the material forming the bottom of any excavation, while acceptable to the S.O. at the time of his inspection, subsequently become unacceptable to him due to exposure to weather conditions or due to flooding or have become puddled, soft or loose during the progress of the Works, the Contractor shall remove such damaged, softened or loosened material and excavate further by hand. Such further excavation shall be held to be Excess Excavation.

8.19 Filling to Embankments and Backfilling to General Excavation

Excavated material including imported material used as filling or backfilling to excavations or completed structures or as fillings to embankments or to raise the ground level shall be free from clods and lumps and shall be approved by the S.O. The approved material shall be placed in layers not exceeding 225 mm depth before compaction and shall be compacted to a dry density not less than 90% of the maximum dry density obtained in Test 11 of BS 1377 except for the top 3m of the embankment filling and filling under structures where the minimum dry density shall be 95% of the maximum


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dry density. Where necessary the Contractor shall adjust the moisture content of the fill or backfill material either by drying out or adding of water. After such drying out or adding of water, the fill shall be thoroughly mixed until the moisture content is suitable.

Should the material being placed as filling or backfilling, while acceptable at the time of selection, become unacceptable to the S.O. due to exposure to weather conditions or due to flooding or have become puddled, soft or segregated during the progress of the Works, the Contractor shall at his own expense remove such damaged, softened or segregated material and replace it with fresh approved material. The Contractor shall when placing the filling or backfilling make due allowance for any settlement that may occur before the end of the Defects Liability Period . Where necessary, the Contractor shall at the end of the Defects Liability Period remove any excess material or make up any deficiency of backfilling or filling to the specified levels.

8.20 Trenches Not to be Left Open

No length of trench excavation shall be started until the pipes to be laid in that length are available on Site. Trench Excavation shall be carried out expeditiously and, subject to any specific requirements of the Contract, the refilling and surface reinstatement of Trench Excavation shall be commenced and completed as soon as reasonably practicable after the pipes have been laid and jointed. Joint holes may be left unrefilled until the joints have been air tested and moulded or protected. Pipelaying shall follow closely upon the progress of Trench Excavation, and the Contractor shall not permit the carrying out of Trench Excavation in unreasonably excessive lengths until pipelaying matches up with the progress of Trench Excavation. The Contractor shall take precautions to prevent flotation of pipes in locations where Trench Excavations may be flooded and these precautions may include the partial refilling of the trench leaving pipe joints exposed while awaiting tests of the joints. If the S.O. considers that the Contractor is not complying with any of the foregoing requirements he may prohibit further Trench Excavation until he is satisfied with the progress of laying and refilling of Trench Excavation.

8.21 Refilling Trench Excavation

Trench Excavation shall normally be refilled using suitable materials selected from excavations carried out within two hundred metres of the length to be refilled, or imported fill materials. The excavated material shall be soft material free from stones of all kinds shall be deposited in 150 mm layers and thoroughly rammed under and around the pipe with suitably shaped rammers working alternately on either side of the pipe (particular care being taken to avoid damage to the pipe and any sheathing) until the trench has been refilled up to the swell of the pipe, and thereafter until the soft filling has been carried up at least 300 mm above the top of the pipe.


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The remainder of the refilling may consist of coarse material free from boulders and clods of earth larger than 150 mm in size provided that the compacted refill is, in the opinion of the S.O., sufficiently dense to prevent material from the superimposed layers being washed into the voids in such refill. This coarse material shall be spread in layers of depth not greater than 225 mm and be thoroughly rammed by an approved mechanical rammer or pan vibrator. The coarse filling is to be carried up to the level at which surface reinstatement is to commence or to such level at which the surface reinstatement of the whole of the topsoil, will leave the finished work sufficiently "proud" to allow for future settlement to the original ground level.

The reinstated surface shall be rolled with a two-tonne roller when

the material is dried. Any part of the reinstated surface that settled beyond the adjacent original ground level the Contractor shall have to make good of the settlement to avoid formation of drains or gulleys within the refilled trenches.

Sand backfilling to trench excavation shall be provided as shown in drawing or as directed by the S.O. The sand material shall be deposited in 150 mm layers on both sides of the pipe simultaneously and thoroughly compacted and around the pipe working alternately on either side of the pipe until the trench has been filled up to 150 mm above the top of the pipe except for pipes laid in roads where the sand backfill shall be brought up to the base course formation level. The sand filling material shall be compacted either by a suitable mechanical vibrator and/or by an approved system of water jet. The topping of the refilling shall be in accordance with the remainder of the refilling for trench excavation as described above for backfill with excavated material. Sand filling such as mining sand or river sand filling within the grading limit will be accepted for use. Quarry dust shall not be considered for use as filling material. Where necessary the Contractor shall adjust the moisture content of the refill material either by drying out or by adding water to assist the compaction of the material. Should the material to be placed as refilling, while acceptable at the time when approved, become unacceptable to the S.O. due to exposure to weather conditions or due to flood or have become puddled, soft or segregated during the progress of the Works, the Contractor shall not use such material for refilling trenches and shall only use fresh approved material.

Trench Excavations shall be refilled with concrete to the heights and limits as shown on the Drawings and where directed by the S.O.


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8.22 Soft Refill Material - Special Measures

Where in the opinion of the S.O. sufficient supply of the aforesaid soft material for trench refilling cannot reasonably be obtained from Trench Excavations within two hundred metres of the length of trench to be refilled without resorting to sieving or other special means then the S.O. shall order the Contractor:- (a) To carry out such work as may be necessary to sieve out stones.

(b) To transport suitable soft material from Trench Excavations at

distances greater than two hundred metre from the length to be refilled ("overhaul").

(c) To excavate soft material from suitable borrow areas and transport it

to the length of trench to be refilled, and the Contractor shall do any or all these things as directed.

And the Contractor shall do any or all these things as directed.

8.23 Temporary Spoil Tips on the Site

Temporary spoil tips may be used to store excavated material as required and shall be arranged by the Contractor subject to the S.O.'s approval having regard to any particular requirements of the Contract. Only material which is approved by the S.O. shall be placed in the temporary spoil tips, topsoil being placed in separate spoil tips where so ordered. No tree trunks, stumps, roots, branches or rubbish of any kind shall be placed in spoil tips. Temporary spoil tips shall be so shaped as to maintain stability and good drainage at all times.

8.24 Treatment of Material from Excavation

Subject to any specific requirements of the Contract, the Contractor shall make his own arrangements for the temporary storage of any excavated material which is required for use in refilling Trench Excavation, and backfilling to general excavation including any necessary double handling. In this connection the Contractor shall have regard to the working areas available to him for the construction of the Works. Any temporary tips alongside the excavations shall be to stable slopes and heights. Where the nature of the excavated material is suitable the Contractor's temporary storage as aforesaid shall include for the separate storage as the S.O. may direct of any of the various grades of material hereinafter specified for the refilling and surface reinstatement of excavations, namely, soft material, coarse material, hard material and topsoil. The Contractor shall ensure that no excavated material which is suitable and is required for re-use in the Works is disposed off outside Site.


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Any excavated material not required or not suitable for use in the Works shall become the liability of the Contractor and he shall be entirely responsible for its removal from the Site and for its ultimate disposal. The Contractor shall comply with all the regulations for the disposal of surplus excavated materials off the site including the payment of royalties, fees, etc, which may be imposed by the relevant Authorities.

8.25 Surface Reinstatement in Road Verges, Fields, etc.

Where Trench Excavation is in road verges, fields and grassed areas, the turf previously removed will suffice for surface reinstatement providing that the grass has not been killed during stacking and that the surface is free from all loose stones. After refilling Trench Excavation as specified, the Contractor shall replace all topsoil previously removed and it shall be evenly distributed and levelled over the full extent of the stripped area. The working space occupied by the Contractor which was originally covered with grass if destroyed during the course of construction shall be covered with 75 mm of topsoil, close turfed and maintained until the new grass is properly established at the Contractor's expense. Other areas not originally covered with grass shall be restored to their former state. Road verges shall be restored to their original width and to a minimum fall of 1 in 24 away from the road and towards the ditch (if any). Restoration of the dip shall be carried out unless the fact that no dip existed prior to pipelaying has been recorded in writing and agreed to by the S.O. The Contractor shall restore all surfaces in a condition not inferior to that which existed prior to commencement of works. Any damage to the metalled road due to pipelaying work alongside road verges or shoulders shall be reinstated to the satisfaction of the authority concerned at no extra cost to the Employer.

8.26 Works in Roads and Road Reserves

Where work is carried out within road reserve, the Contractor shall comply fully with all regulations and requirements in force in that place by all relevant local and public authorities (hereinafter referred to as Authorities). The times of working allowed by the Authorities may or may not fall within day light hours or within the normal working hours of the Authorities. The Authorities may impose charges for works carried out on road verges and metalled roads and the Contractor shall pay the Authorities and recover the cost under the appropriate items in the Bill of Quantities.


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8.27 Surface Reinstatement in Roads and Footpaths

Surface reinstatement of roads and footpaths shall be restored to the approval of the S.O. and to the requirements of the Authorities concerned or the owner or tenant. Any settlement or defects prior to final surface reinstatement shall be made good by the Contractor to the satisfaction of the S.O. Where the pipe trench crosses or is along tarmacadam roads and footpaths belonging to private owners or Authorities, the pipe shall be surrounded with sand and topped up with 375 mm thick of crusher run material followed by 100 mm thick of dense bituminous mix comprising 60 mm thick binder course and 40 mm thick wearing course. The crusher run and binder course surfaces shall receive a layer of tack coat before the application of binder course material and wearing course materials. All fill materials shall be compacted by approved means. The consolidated surface shall be brought up to the same level or the adjoining road. Any subsidence shall be filled in by the Contractor using the same materials. The road shall be kept continuously at its proper level to the satisfaction of the S.O. and the Authorities from the date of filling in the trench until the surface is finally restored. All materials for this reinstatement and subsequent maintenance shall be supplied by the Contractor.

When any section has been reinstated as specified the Contractor shall notify the S.O. who in the presence of the Contractor shall inspect the length of reinstated trench. The S.O. shall at this inspection indicate any further reinstatement required and the Contractor shall complete this work to the satisfaction of the S.O. and the authority concerned within fourteen days of the inspection. Acceptance of reinstatement by the S.O. or the Authorities at this inspection shall not relieve the Contractor of his responsibility for the maintenance of surfaces as specified above.

8.28 Payment for Road Restoration

Items in the Bill of Quantities for Restoration of Metalled Roads except where expressly stated otherwise shall apply to road reinstatement. The charges if any imposed by the Authorities for work carried out on metalled roads shall be deemed to be included in the relevant items in the Bill of Quantities under Restoration of Metalled Roads.

Where the restoration is to be carried out by the Contractor, measurement shall be in accordance to the Bill of Quantities provided.

Where the restoration is to be carried out by the Authorities, the Contractor shall comply fully with all regulations and requirements as stipulated by the Authorities and such restoration shall be deemed to have been restored by the Contractor. The Contractor shall be paid in accordance to the appropriate rates in the Bill of Quantities. Temporary reinstatement prior to final restoration shall be measured separately in addition to permanent restoration.


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If after due notice to the Contractor calling his attention to the necessity for further reinstatement of any trenches across roads and footpaths, he has failed to make good the reinstatement, the Government or the appropriate Authorities may proceed with such repairs and the cost of such reinstatement shall be deducted by the Government from any payments due to the Contractor. Towards the end of the Defects Liability Period the S.O. will inspect the pipeline route in the presence of the Contractor. In the event that final road reinstatement is to be carried out by the Authorities concerned, the Contractor shall carry out temporary reinstatement for the vehicles to pass over it. The temporary reinstatement includes the trench to be refilled with sand, topped with 375 mm thick of crusher run material and followed by a layer of tack coat and 40 mm thick of dense bituminous mix wearing course. All filled materials shall be compacted by approved means. The Contractor shall carry out final reinstatement of public roads and footpaths only if he is instructed by the S.O. Otherwise final reinstatement of these roads will be carried out by the Authorities as and when agreed between the Authorities, the S.O. and the Contractor. The Contractor shall pay the Authorities and shall recover the cost under the appropriate items in the Bill of Quantities. No quantities of final reinstatement beyond the limits of Trench Excavation specified or reinstatement due to Excess Excavation, settlements adjacent to Trench Excavations or damage to road surfaces in the course of pipelaying shall be measured for payment.

8.29 Other Structures in the Pipeline

The Contractor shall carry out further excavation as may be necessary to accommodate structures such as thrust blocks and valve chambers. Such excavation shall include for disposal of surplus material and, where appropriate, for backfilling round the structures.

8.30 Land Drains

Where land drains, mole drains or field drains are severed by Trench Excavation they shall be kept in effective temporary operation during construction of the pipeline. The Contractor shall submit to the S.O. for approval a temporary drainage arrangement to ensure the water course is not hindered during the construction. The drain on either side of the Trench Excavation shall be cut-back for at least 300 mm and temporary pipes of suitable length and diameter shall be jointed to the existing drain and laid resting with the ends on solid ground with suitable stopping to prevent the subsequent run of land drainage water into the pipe trench. During trench re-filling, the refill material shall be carefully placed and thoroughly compacted under the temporary pipes to give them adequate support.

Should any existing sub-soil or field drains be uncovered during general excavation, the Contractor shall either carefully replace them when


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backfilling, or if this is impracticable shall divert them to new drains or ditches, or otherwise relay them as the S.O. may direct. At the appropriate stage of refilling the Trench Excavation the drains shall be permanently restored to the satisfaction of the S.O.

8.31 Care of Existing Services

Information relating to the positions of all existing mains, cables, culverts, pipes, drains or services of any kind shall be ascertained by the Contractor. Notwithstanding any information which may be furnished by the S.O., the Contractor shall be responsible for ascertaining from his own inspection of the Site and from the respective supply authorities and other public authorities the positions of all mains, pipes and cables whether underground or overhead, within or near the Site. Where services are shown on the drawings or where there is evidence of services in the ground, the Contractor shall also determine their exact positions. In addition the Contractor shall watch for and determine the position of any service which may not have been marked. Where Trench Excavation is carried out close to or across the line of sewers, pipes, cables and other services the Contractor shall provide temporary adequate supports to secure the services and where such sewer, pipe, cable or other service is temporarily displaced or disturbed it shall be restored to its original state. If restoration of any service to its original state cannot be achieved then it shall be replaced and made good. The cost of excavating around any service which crosses the trench, and of temporarily supporting it while pipelaying is undertaken, shall be deemed to be included in the rates for excavation. All damage to services shall be made good to the satisfaction of the S.O. and the authorities concerned. The cost of making good any damage shall be deemed to be included in the rates for excavation. In the event that any damaged service shall only be repaired by the authority concerned, all costs whatsoever relating to the repairing of the damaged service undertaken by the authority shall be at the Contractor's expense. Where damage to a service had already existed prior to excavation or other work, repair of the damaged service shall be undertaken by the Contractor, if so ordered by the S.O. and the Contractor shall be paid on Daywork for repairing such service. Where in the opinion of the S.O., construction of the pipeline cannot reasonably be carried out unless the sewer, pipe, cable or other service is permanently severed or permanently diverted or permanently supported the Contractor shall undertake such work if so ordered by the S.O. Any such work if carried out shall be to the satisfaction of the S.O. and of the authority concerned and shall be paid for at Daywork where necessary and at the appropriate Contract Rates. Where pipes are laid under culverts they shall, subject to other provisions in the Contract and to the S.O.'s instructions, be given a concrete surround extending for 600 mm clear on each side of the culvert, and a concrete half haunch to the culvert shall be provided over the width of the trench cast directly on top of the concrete surround. The cost of all work in removing any piles and concrete bed under culverts and of temporarily supporting the


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culvert during pipelaying shall be deemed to be covered by the rates for the items in the Bill of Quantities for pipe crossing under culverts.

8.32 Hedges, Fences and Walls

Where the Trench Excavation passes under barriers such as hedges, fences and walls the Contractor shall, as a temporary measure during construction of the pipeline, provide temporary fencing for any parts of such barriers as have had to be removed. After trenches have been refilled and surfaces reinstated, the Contractor shall carry out work as the S.O. may order for permanent restoration of such barriers. In the case of a hedge the section removed shall be replaced by new plants of the appropriate variety and where ordered by the S.O. the plants shall be protected from livestock on both sides by an adequate post and barbed wire fence. During the Defects Liability Period all hedges replanted in the above manner shall be inspected and any dead plant replaced by the Contractor.

8.33 Crossing Watercourses, Etc

Where the pipeline crosses underneath rivers, culverts and other watercourses the Contractor shall be deemed to have allowed for all the additional measures necessary for the proper construction of the pipeline including maintaining the full flow of water.

8.34 Measurement of General Excavation

Items in the Bill of Quantities for "excavation" except where expressly indicated otherwise shall apply to excavation where Bulk, Incidental or Trench in any material and shall not only include for all work in connection with excavation but shall also include for all loading and transportation, temporary fencing, double handling, filling, backfilling and for disposal of surplus materials, the means of disposal being the Contractor's responsibility. Items for "Excavation in Rock" measured Extra Over (E.O.) other excavation items, shall include for any allowance the Contractor considers necessary to cover overbreak and the making good thereof. All work in connection with excavation and subsequent disposal of excavated material as specified shall be valued by measurement of such items as are set forth in the Bill of Quantities for "excavation" and where appropriate of the further E.O. items for Rock. All such measurements unless otherwise specified shall be the net volume of the voids to be formed by the removal of material excavated to the specified levels and limits described herein or shown on the Drawings, no allowance being made for bulking. No separate payment shall be made in respect of Excess Excavation or the backfilling thereof. Incidental Excavation for removal of unsuitable material shall (unless it is held to be Excess Excavation) be measured as the volume ordered by the


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S.O. to be excavated beyond the nominal dimensions of general excavation and shall include for the disposal of the excavated material off the Site and for refilling the excavation with approved material emanating from excavation elsewhere or refilling with the grades of concrete as may be reasonably ordered by the S.O. Excavation in borrow areas for refilling of trenches shall include for loading and transporting the excavated material from borrow areas which are not more than two hundred metres from the length of trench to be refilled. The net volume of voids ordered to be refilled within the normal width of trench excavation shall be measured for payment. Where such distance is in excess of two hundred metre ("Overhaul distance"), the product of the overhaul distance and the net volume of voids to be refilled within the normal width of the trench excavated shall be measured as extra over (E.O.) excavation for payment. Excavation in borrow areas for filling to embankments for pipelines or for raising the ground level along the pipeline routes as directed by the S.O. shall include for loading and transporting the excavated materials from borrow areas which are not more than two hundred metres from the locations to be filled. Items in the Bill of Quantities for excavation and filling shall be measured as the volume after compaction of the fill material placed to the limits and depths shown on the Drawings or as directed by the S.O. The Contractor shall be deemed to have made his own allowance for compaction and for any "loss" of material into the ground below the embankment. Where the distance as aforementioned is in excess of two hundred metres ("overhaul distance") the product of the overhaul distance and the volume after compaction of the fill material placed to the limits and depths shown on the Drawings or as directed by the S.O. (as defined as aforementioned) shall be measured as extra over (E.O.) excavation and filling for payment.

8.35 Measurement of Trench Excavation

Items for Trench Excavation shall apply to excavation in any material and shall include not only for all work in connection with excavation but also for refilling of trenches spreading and compacting excavated material over pipeline reserve as directed and for disposal of surplus material, for temporary fencing and, in fields, for the stripping and subsequent reinstatement of the top surface all as specified. Trench Excavation shall be measured by length along the centre line of the pipeline at the various depths stated in the Bill of Quantities and the Contractor shall be deemed to have made his own assessment (subject to any specific requirements of the Contract) of the widths of Trench Excavations necessary for the proper construction of the Works including all allowances to provide support for the excavations, to accommodate joints and bends in the pipeline and to provide working space. The length of Trench Excavation shall be measured through and including any space occupied by manholes, chambers, thrust blocks and the like. No extra payment shall be made for trenches which are curved in plan or elevation. The depth of Trench Excavation for pipes shall be measured normal to the profile of the ground along the centre line of the trench from the original


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ground level or where appropriate from the ground level remaining after the completion of any general excavation down to the specified invert level of the pipe plus the thickness of the pipe barrel and plus, where appropriate, the specified thickness of bedding for the pipe. The sides of Trench Excavation shall be deemed to be vertical in all materials and the nominal widths defined in Clause 8.12 shall apply to any depth of trench and whether or not bedding or surround to the pipe is specified.

Trench Excavation and all work in connection therewith as specified shall be valued by the measurement only of such items as are set forth in the Bill of Quantities, except where expressly provided for otherwise by the inclusion in the Bill of Quantities of any of the following further items:- Incidental Excavation for structures situated in the pipeline shall be measured only to the extent that the net excavation required to accommodate the structures falls outside the nominal dimensions of the Trench Excavation. Incidental Excavation for removal of unsuitable material shall (unless it is held to be Excess Excavation) be measured as the volume ordered by the S.O. to be excavated beyond the nominal dimensions of Trench Excavation and shall include for the disposal of the excavated material off the Site and for backfilling the excavation with approved material emanating from Trench Excavation elsewhere or for backfilling the excavation with the grades of concrete ordered by the S.O. Rock, measured E.O. Trench Excavation items, shall be measured as the volume of Rock within the nominal limits of Trench Excavation in Rock. When measured E.O. Incidental Excavation items it shall be measured as for those items. Excess Excavation and the backfilling thereof shall not be measured for payment. Trench Excavations in roads and in footpaths as specified shall be measured (E.O. Trench Excavation) as the area calculated by multiplying the length of trench so excavated by its nominal width. The stripping of the top surface and the surface reinstatement of Trench Excavation in fields shall be included in Trench Excavation and shall not be separately measured. Crossing hedges, fences and walls shall include for all temporary measures for dealing with such barriers as specified and shall be measured as the length of such barriers so dealt with within the nominal width of Trench Excavation. Any permanent measures required by the S.O. shall be ordered by him as additional work. Crossing rivers culverts and other watercourses shall include for all additional measures necessary to make the crossings as specified. Only such crossings as may be itemised in the Bill of Quantities will be measured (E.O. Trench Excavation) for additional payment. The length to be measured for payment for crossing natural watercourses shall be defined as the width of


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the waterway along the pipeline at the time of construction of the crossing (except flash floods and floods). Overhaul of refill or excavated materials (E.O. Trench Excavation or Excavation in borrow areas) shall apply in cases where the S.O. orders material to be transported from locations of excavation which are more than two hundred metres from the areas to be filled.

8.36 Measurement of Filling for Embankment

Items in the Bill of Quantities for "forming embankment" for roadworks, for raising the ground level of the Site or for filling under structures shall include for the supply, spreading, compacting and shaping all as specified. Filling for embankment shall be measured as the volume after compaction of the fill material placed to the limits and depth shown on the Drawings or ordered by the S.O. The Contractor shall be deemed to have made his own allowance for compaction and for any "loss" of material into the ground below the embankment.

8.37 Payment for Trench Excavation and Restoration

Payment for trench excavation shall be made in two stages, as follows :-

(a) 75% of the total amount due will be paid on completion of pipelaying. (b) The remaining 25% for any length, will be due on completion of

restoration of the final surface, including reinstatement of all surface damage, completion of chambers, thrust blocks, etc.

Payment for the second stage shall be due only after restoration of any length has been inspected and approved by the S.O. Payment for the separate items in roads, footpaths, etc. will be made at the same time as the second stage payment for excavation.

8.38 Top Soiling

Topsoil shall be evenly spread and trimmed over embankments and other areas to the slopes and levels shown on the Drawings or ordered by the S.O. The depth after spreading and trimming shall be 75 mm unless otherwise directed, measured normal to the surface. All clods and lumps shall be broken up and any rubbish, stones, roots and weeds shall be removed.

8.39 Turfing

The Contractor shall establish grass by continuous or spot turfing as directed. Each turf shall be approximately 200 mm by 200 mm by 50 mm thick. Turf shall be laid immediately after delivery to Site.


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Where turf is laid on slopes steeper than 1 on 3.0, each turf shall be securely pegged down with two cleft wooden pegs 150 mm long. All turfed areas shall be lightly rolled with an approved roller or punned immediately after laying, and shall be watered regularly until the grass has been established. Grass areas affected by trench excavation shall be restored as specified above.

8.40 Measurement of Top Soiling and Turfing

Items where included in the Bill of Quantities for spreading topsoil shall include for obtaining topsoil from spoil tips on the Site, or from an approved source off the Site, hauling and spreading all as specified. Items where included for turfing shall include for all work in connection with turfing as specified, and for cutting and trimming and weeding at least once two months until the end of the Contract Period. Topsoiling shall be measured as the areas so treated, and except where expressly indicated otherwise items shall apply to sloping as well as to horizontal surfaces. Topsoiling and turfing of re-filled trenches shall be included in items for Trench Excavation and shall not be separately measured for payment.

8.41 Payment for Turfing

Payment for continuous turfing shall be the area covered by the turves provided. Where spot turfing is required the distance between the centre lines of divots in the form of a triangular pattern shall not exceed 500 mm and the percentage of the area covered shall be agreed and payment made on the total area spot turfed multiplied by the percentage. Turfing will be paid for in two parts:-

(a) At fifty percent of the Contract Rate when the turfing has been

carried out; (b) At fifty percent of the Contract Rate when the S.O. is satisfied that

the grass has established itself.

Where grass fails to establish itself, the Contractor shall turf the relevant area again at no extra cost to the Government.

8.42 Payment of Fees to Authorities

The Contractor shall pay to all Authorities all deposits, fees and charges required to be paid in relation to the execution of the Works or to any Temporary Works.


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If after due notice to the Contractor calling his attention to the necessity for the payment of fees and/or charges to the Authorities the Contractor has failed to make payment, the Government shall be entitled to pay such fees and/or charges direct to the Authorities concerned out of any moneys at any time due to the Contractor under the Contract and such payment shall be deemed to be payment made to the Contractor under and by virtue of the Contract. The cost of all fees and charges payable by the Contractor shall be deemed to be included in the Contract Rates unless otherwise expressly provided for in the Bill of Quantities.


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.

SECTION 9.0 –

PILING



9.0 PILING 9.1 General

Unless otherwise specified, all piling shall conform in all respects to the Civil Engineering Code of Practice CP 2004 `Foundations' issued by the `British Standards Institution, London'.

The type of pile to be used at each structure, where piling is required, shall be as indicated on the Drawings or as directed by the S.O.

9.1.1 Ground Conditions It shall be the Contractor's responsibility to carry out further sub-surface

investigation if he has any doubt about the available information or if he considers further information necessary or desirable. Such investigation by the Contractor shall be entirely at his own expense and shall have the S.O.'s prior approval in writing.

The S.O. shall be supplied free of charge with two (2) copies of the results of

all such investigation by the Contractor. In addition to submitting the records required, the Contractor shall report

immediately to the S.O. any circumstances which indicate that the ground conditions differ from those expected by the Contractor from his interpretation of the results of soil investigation carried out by SAJH and which affect adversely the bearing capacity of the pile.

The Contractor's attention is, however, drawn to the fact that suitable

founding strata may be encountered at depths which require the actual installation of different lengths of pile and which may give rise to considerable variation within any particular site or pile groups.

9.1.2 Setting Out The pile layout and the number of piles shown on the Drawings are

provisional only. The Contractor shall, before commencing any part of the piling work ascertain from the S.O. the layout of the piles required.

The Contractor shall set out the piles from the main grid lines of the

proposed structure or such base lines as shall be agreed with the S.O. The main setting out for piles shall be completed prior to commencement of piling. Secondary or individual pile setting out shall be completed and agreed with the S.O. not less than 24 hours prior to commencing work on the piles concerned. All main setting points, lines, stations and the like shall be suitably protected, maintained and undisturbed.

For a pile cut-off at or above ground level the maximum permitted deviation of the pile centre from the centre point shown on the Drawings shall not exceed 75mm in any direction. For a pile cut off below ground level an increase in the verticality tolerance is permitted up to 1 in 75 from the finished pile.


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9.1.3 Piling equipment The piling equipment shall be capable of speedily and efficiently installing

piles of the specified types, sizes, lengths and safe working loads. The type of piling equipment shall be suitable for the type of piles to be

driven and shall be that of a system which produces the minimum noise during driving.

The Contractor shall provide sufficient number of units to ensure completion

of piling work according to programme. Before any piling work is commenced, the Contractor shall submit to the

S.O. full details of the pile driving equipment and the method of carrying out the work which he intends to use. Such information shall include a full description of the piling frame, hammer, helmet and packing and of a method of handling and pitching piles and supporting them during driving, and of the proposed driving procedure set to give penetration to the required level and of the proposed set for the working load on the pile and the method of calculating it. Any revisions to these proposals which, in the light of ensuing experience, appear desirable, shall also be submitted for the approval of the S.O. prior to implementation of said revisions.

The piling frame shall be of sturdy construction, supported on an adjustable

base, securely guyed and with ample toggle connections to leaders so that the pile is firmly held at all times. The type and weight of hammer shall be to the approval of the S.O. and the weight of the hammer shall be at least half that of the pile or otherwise specified. In general, a heavy hammer with a short drop should be used in preference to a light hammer with a longer drop. Single or double acting diesel or air operated hammers may also be employed. The Contractor shall submit confirmation of hammer energy per blow to the satisfaction of the S.O. All plant being used shall be maintained in a satisfactory condition and any items suffering wastage or damage shall be promptly replaced or repaired.

No piling shall be carried out without the approval in writing of the S.O. of

the equipment and method of working and any revisions to these as described above, and the Contractor shall submit all of his proposals at least three weeks before the date on which he intends to use the plant on the Site.

9.1.4 Programme The Contractor shall submit to the S.O. his proposed programme for the

execution of the piling work at least seven days before commencement of the work. In addition, the Contractor shall inform the S.O. daily of the programme of piling for the following working day and shall give adequate notice of his intention to work outside normal hours, if this has already been approved by the S.O.


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9.1.5 Pile driving Unless otherwise specified, pile driving shall be as specified hereunder.

The driving equipment to be used shall be of such type and capacity to the approval of the S.O. If drop hammer is used, it shall be of a free fall type and the weight of the hammer shall be as specified in CP 2004.

Piles shall be pitched accurately in the positions as shown on the Drawings.

At all stages during driving and until the pile has set or driven to the required length, all exposed piles shall be adequately supported and restrained by means of leaders, trestles, temporary support or other guide arrangements to maintain position and alignment and to prevent buckling and damage to the piles.

Each pile shall be driven continuously until the specified set and/or depth

has been reached. However, the S.O. may permit the suspension of driving if he is satisfied that the rate of penetration prior to the cessation of driving will be substantially re-established on its resumption or if he is satisfied that the suspension of driving is beyond the control of the Contractor.

A follower (long dolly) shall not be used for driving end bearing piles. It may

be used for driving frictional piles with prior approval of the S.O. The contractor shall inform the S.O. without delay if an unexpected change in driving characteristics is encounted.

Where required by the S.O. set shall be taken at approved intervals during

the driving to establish the behaviour of the piles. A set shall be taken only in the presence of the S.O. unless otherwise approved. The Contractor shall provide all facilities to enable the S.O. to check driving resistances.

Retrieve checks, if required, shall be carried out in accordance with an

approved procedure. A detailed record of the driving resistance over the full length of each pile

shall be kept. The log shall record the number of blows for every 300mm of pile penetration.

The final set of a pile other than a friction pile, shall be recorded either as

the penetration in millimetres per 10 blows or as the number of blows required to produce a penetration of 25mm.

When a final set is being measured, the following requirements shall be

met:-

a) The exposed part of the pile shall be in good condition, without damage or distortion;

b) The dolly packing shall be in sound condition;

c) The hammer blow shall be in line with the pile axis and the impact

surfaces shall be flat and at right angle to the pile and hammer axis;

d) The hammer shall be in good condition and operating correctly;

e) The temporary compression of the pile shall be record if required.


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Piles shall be driven in an approved sequence to minimise the detrimental effects of heave and lateral displacement of the ground. When required, levels and measurements shall be taken to determine the movement of the ground or any pile resulting from the driving process. If any pile rise occurs as a result of adjacent piles being driven, the Contractor shall submit to the S.O. his proposals for correcting this and to avoid the same in subsequent work.

9.1.6 Preliminary and Working Test Piles A preliminary test pile is a pile installed at the Site before the

commencement of the main piling work for the purpose of establishing the driving criteria for subsequent working piles and for confirming the adequacy of the pile design, dimensions and bearing capacity. Preliminary test piles shall be of the same materials and driven or formed with the same plant and in the same manner as the working piles.

A working test pile is a pile which is installed as part of the permanent

foundation works. No work on working test piles shall proceed until the testing of the preliminary test pile has been completed to the satisfaction of the S.O.

After testing of trial piles the S.O. will direct the lengths of piles to be

supplied or manufactured. He will also direct the lengths of any extension piles to be supplied or manufactured.

9.1.7 Load tests The Contractor shall submit to the S.O. for approval complete details of the

testing equipment he intends to use for testing piles. All loading tests shall be carried out and comply with the conditions as described in Section 9.4 of the Specification on pile testing.

The S.O. will select the location of the preliminary test piles and the working

piles to be load tested. The S.O. will decide upon the necessity for testing working piles, and may

select for testing one or more working piles which the Contractor shall drive in advance of the remaining piles at the Site. Piles selected for this purpose shall be constructed or driven, with the same equipment as proposed for the main piling work, to the depths required by the S.O. The remaining piling at the Site shall not proceed until the testing of the advance working pile has been completed to the satisfaction of the S.O. and meets the requirements for acceptance specified herein. The S.O. will also instruct the testing of further piles during the course of the piling work.

9.1.8 Piling Personnel Piling work shall be carried out under the direction of a competent

supervisor experienced in the particular system of piling to be used. He shall be employed full time for the duration of the piling operations and his appointment shall be subject to the approval, in writing, of the S.O. before


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the commencement of piling work. The Contractor shall also employ at each site a specially qualified foreman together with the necessary gang of trained personnel and labour experienced in the installation of the piles.

9.1.9 Piling Records The Contractor shall keep a record of all piles driven at the Site. The record

shall contain such details as specified or otherwise as required by the S.O. The Contractor shall also submit to the S.O.'s Representative within 24

hours a copy of the field record of the piling work done each day. On completion of all piling work at each site, the Contractor shall prepare

and submit to the S.O.'s Representative two (2) sets of a complete drawings showing details of all piles driven at the Site.

All pile test records shall be considered as confidential and shall not be

disclosed by the Contractor to any third party without the express permission in writing of the S.O.

9.2 Precast Reinforced Concrete Piles 9.2.1 General Precast reinforced concrete piles shall conform to the details shown on the

Drawings. Concrete reinforcement and formwork shall be in accordance with the appropriate section of the Specification. Main reinforcing bars shall be supplied in one complete length; should this prove impracticable separate lengths shall be effectively coupled mechanically or lapped as specified. Spacer forks shall be of cast iron, mild steel or other material or type and shape approved by the S.O.

Pile shoes shall consist of "chilled hardened" cast iron points and mild steel

straps cast into the points and be in accordance with the Drawings or otherwise approved by the S.O.

9.2.2 Pile Casting Before any reinforced concrete pile is cast, the Contractor shall submit to the

S.O. for approval a description, accompanied by Drawings and programme, of the methods he proposes to adopt for handling and driving piles, giving full particulars of all plant and equipment to be employed. Notwithstanding any approval of the Contractor's proposals by the S.O., the Contractor shall be and remain solely responsible for the successful installation of the piles.

The length of each pile unit cast shall be as detailed on the Drawings. Pile

extensions shall be cast in suitable lengths to suit Site conditions. Where required load tests shall be carried out to assess bearing capacity.

Pile units shall be cast in one continuous operation on a horizontal platform

in steel or wooden moulds and no interruption shall be permitted. The


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moulds shall be thoroughly cleaned before casting, and the assembled reinforcement lowered into the mould and held in position from the top. Lifting holes shall be formed, during casting, in the position and in according with the details shown on the Drawings.

The mild steel end plates for jointing piles and pile extensions shall be

placed in the ends of the moulds before placing concrete. These plates shall be aligned with great care to ensure that they are truly perpendicular to the axis of the pile. Any pile or pile extension cast with an end plate not truly perpendicular to the axis of the pile shall immediately be rejected. After casting the piles, formwork shall be removed in the presence of the S.O. Failure by the Contractor to observe this requirement may result in rejection of the pile concerned. Any pile showing signs of honeycombing or other defects on removal of the formwork shall be repaired to the satisfaction of the S.O. before it is used in the Works.

9.2.3 Curing, Stripping and Stacking Piles made with ordinary Portland cement shall be kept damp for a period of

14 days after casting. Side forms may be stripped 4 days and bottom boards 12 days after casting, provided the piles are kept supported on level blocks spaced at not more than 1.8m centres. After 21 days piles may be lifted and removed to a suitable stacking area but they may not be driven until they are at least 4 weeks old. Each pile shall be clearly marked with the date of casting and all stacks shall be arranged to facilitate the removal of piles for driving in their correct order of age. For piles made with Rapid Hardening cement the above periods shall be modified as directed by the S.O.

9.2.4 Handling Storage and Transport of Piles Piles shall be handled with great care, lifted using only the proper lifting

holes and supported in the manner as approved by the S.O. Any departure from the approved method of lifting the piles shall be approved by the S.O. before use. Piles shall be stored on adequate bearers so arranged that they may be picked up for transport without damage.

Care shall be taken to ensure that bearers are level transversely so that piles

are not subjected to undue stress. Handling and delivery of the piles shall be done in a manner which avoids excessive bending stresses. The method of transport shall be subject to the approval of the S.O.

Any piles cracked or damaged during handling shall not be used in the

Works and shall be replaced by the Contractor at no extra cost to the Government.

9.2.5 Pitching and Driving Piles shall be pitched accurately in the positions and driven to the

appropriate lines and levels shown on the Drawings. During and after completion of piling the pile head shall not be more than 75mm off centre in any one direction from its required position. Piles shall be suitably constrained to maintain their correct position by means of guys or guides.


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No piles which have been deflected from the permitted tolerance shall be forcibly brought back to correct alignment. Where piles are driven below the level of the bottom of the leads of the pile frame, extension leads shall be fitted. The use of a follower or dolly will not be permitted except with the written approval of the S.O. During driving the heads of the piles shall be protected by a helmet of cast steel or mild steel fitting closely around the pile. A packing of coiled hemp rope or asbestos fibre, 25mm thick, covering the head of the pile, shall be contained within the helmet and separate the helmet from the head of the pile. The top of the helmet shall be recessed and fitted with a timber stub dolly 300mm long. The packing and stub dolly shall be renewed as often as necessary to prevent damage to the piles. The type of helmet specified above may be modified at the discretion of the S.O. Piles damaged during driving shall be removed and replaced by the Contractor without extra cost to the Government unless the S.O. is satisfied that effective repairs can be made in-situ. The Contractor shall maintain a record of the driving of all piles giving sets and other details required by the S.O. to whom the records shall be submitted on request. All piles shall be driven to such final set or depth as may be approved by the S.O. Immediately after a pile has been completely driven, a record shall be made of the reduced level of the pile head and further checks shall be made on the level of the head after the driving of adjacent piles. Should any pile heave upwards it shall be redriven to its original level or, if necessary, until its specified set is again obtained.

9.2.6 Plant for Pile Driving If a gravity operated hammer is used the weight of the hammer shall be at

least 3 tonnes or 75% of the weight of pile. If, however, conditions at the Site show that this is insufficient, the S.O. may require that a heavier hammer is used. Every hammer shall bear an identification mark and the Contractor shall furnish a weight bridge certificate of its actual weight. The hammer drop shall not exceed 1.5m and at no time during driving shall the centre of the hammer be more than 38mm off pile centre.

If a single acting power operated hammer is used, the limitations on hammer weight specified above for gravity operated hammer shall apply to the moving weight of a single acting power operated hammer.

If a double acting power operated hammer is used, the net energy per blow,

multiplied by the efficiency of the blow shall be at least 25 kilojoules. 9.2.7 Measuring Pile Set The Contractor shall provide suitable means of measuring and recording the

pile set under each hammer blow.


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This may be achieved by using a fixed straight edge held against a sheet of paper affixed to the pile, and running a pencil along the straight edge at the moment of impact to record on the paper the elastic and plastic sets resulting from the blow. The straight edge shall be attached to a fixed frame of heavy timber standing close to the pile.

9.2.8 Extending Piles Piles shall be extended as directed by the S.O. and shall be carried out as

described below. When the pile shall have been driven to within one metre of the pile head

above ground level, the dolly and packing shall be removed and the head of the pile examined for damage. If the pile has suffered no damage, the end plate shall be thoroughly cleaned, free from rust and scale, and filed down to expose bare metal. The end plate of the pile extension shall be similarly cleaned and the extension pitched, placed carefully on top of the pile head, aligned and plumbed. The end plates shall then be joined by a fillet electric arc weld extending completely round all four sides as shown on the Drawings.

After the slag has been chipped from the weld and the weld wire brushed and cleaned, it shall be inspected by the S.O. and, if pronounced satisfactory, it shall be painted with 2 coats of coal tar epoxy of an approved type. Pile driving shall continue when the paint has dried.

If the pile head has suffered damage it shall be repaired by the Contractor to

the satisfaction of the S.O.'s Representative and the cost of all such repairs shall be borne by the Contractor.

The S.O.'s Representative will instruct the Contractor which length of pile

extension to use for extending the piles.

9.2.9 Preparation of Pile Heads After pile driving and load tests (if required) have been completed to the

satisfaction of the S.O.'s Representative, the top of each pile shall be cut down to the correct level, and the steel reinforcement exposed and bent into the required positions, prior to construction of the pile cap.

Where the length of pile left above the required level exceeds the length of

pile cap reinforcement required, the excess length of pile may first be cut at the level which provides the required length of reinforcement.

9.2.10 Load Tests The Contractor shall carry out load tests on precast concrete piles by the

Maintained Load Method as detailed in Section 9.4. Tests shall be carried out on preliminary piles and working piles, as defined

in Section 9.1.7 and as directed by the S.O.


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9.3 Treated Timber Piles 9.3.1 General Timber used for the piles shall not be of a lesser quality than the selected

Structural Grades specified in Section J (Stress Gading) of Part III of the Malayan Grading Rules for Sawn Hardwood Timber. The timber shall be free from rot, fungal or pest attack and any other defects not permitted for its grade.

The dimensions of sawn timber piles shall be within the rate of 2mm less

and 6mm greater than their specified cross-sectional dimensions. The centroid of any cross-section of a sawn timber piles shall not deviate by more than 25mm from the straight line connecting the centroids of the end faces of the standard length of pile.

Where applicable the standard of workmanship shall conform to CP 112. Before commencement of any work, the Contractor shall notify the S.O. the

name of the supplier and manufacturer for approval. Piles shall be supplied in one single length of 6 metres, unless otherwise

approved. 9.3.2 Treatment of Piles The method of treatment shall be full-cell process as described in MS 3.38.

The composition for preservative shall be Type 2 of MS 3.38. The depth of penetration of preservation when determined by the method described in Appendix H of MS 3.38 shall be a minimum of 25mm. The net dry salt retention in the treated part of the timber as determined by the method described in appendix `K’ of MS 3.38 shall be a minimum of 16 kg.m.cu.

The treated timber pile shall be permanently marked with identifications which indicate that it complies with the Specification, manufacturer trade mark, change number and date of treatment, and the length of the pile.

The S.O. may require inspection of the treatment plant to observe and

ensure that the manufacturing process and control testings of the piles are carried out in accordance with the Specification. Records for the actual treatment schedule shall be kept during the treatment process, and the Contractor shall furnish such records for the piles supplied when requested by the S.O.

Before the treated timber pile is accepted for the Works the Contractor shall

obtain from the manufacturer of the treated piles a warranty on approved form which provides that for a ten year period the treated piles shall be free from such fungus and insect attack which may render the supported structures unsound.

9.3.3 Delivery and Stacking of Piles The Contractor shall notify the S.O. of the delivery of timber piles to the Site

and provide the necessary facilities to enable the S.O. to inspect the piles


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and take random sampling for determination of depth of penetration of preservation and the net dry salt retention.

Accepted piles shall be marked and stacked in lengths on paving of drained

hard ground. Each piece of pile shall be stacked clear of the ground and have an air space around it. The piles shall be separated by sticks or blocks placed vertically one above the other and closely spaced horizontally to avoid sagging of the piles. All rejected piles shall be removed from the Site promptly.

9.3.4 Pile Driving and Jointing The pile head shall be adequately protected during driving, so that

“brooming” does not occur. The pile head shall be fitted with toothed metal plates as approved by the

S.O. for protection against “brooming" and splitting during normal driving. In the case of hard driving, unless otherwise approved by the S.O. a metal

helmet shall be fitted to the top of the pile. The top of the pile shall first be trimmed to fit closely into the recess of the underside of the helmet. A hardwood dolly and if necessary, a packing piece shall be used above the helmet.

If during driving the head of the pile becomes excessively broomed or otherwise damaged, the damaged part shall be cut off, and the helmet refitted.

Any pile driven to the required set at a depth of 6.0m or less shall, be in one

continuous length. If jointing is required, pile joints shall be made by using galvanised mild steel

welded boxes 460mm long fabricated from 5mm thick plates unless otherwise shown on the Drawings. The internal dimensions of the box shall be 3mm undersized of the pile cross-sectional dimensions. The joint and the ends of the piles to be jointed shall be constructed, so that the necessary strength and stiffness are developed at the joint.

When fissures appear in a pile during driving, which in the opinion of the

S.O. will affect its strength, the pile shall be rejected and replaced at the Contractor’s expense.

The pile head shall be embedded for a depth of not less than 150mm in the

concrete cap which shall be at least 150mm thick round the pile. 9.3.5 Load Tests If so directed by the S.O. the Contractor shall carry out load tests on treated

timber piles shall be carried out by subjecting a group of the piles to a

When a pile has been driven to the required set or depth, the head of the piles shall be cut off square to sound wood and treated with an approved preservative and a waterproof coating to the approval of the S.O.


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vertical test load, until actual failure of the group takes places. The group of piles shall consist of at least four (4) piles (ie . 2 rows of 2 nos.), and shall be driven at location of the site as selected by the S.O. The piles tested may after wards form parts the foundation of the structure.

At least 48 hours notice of the commencement of each test shall be given to

the S.O. the load test shall only commence after the piles have been driven and left in position for a period of not less than 7 days.

The load test shall be performed before commencing to drive the remaining

piles. From the results of the test (s), the S.O. may direct to vary the number of the piles required.

The pile shall be tested to failure by the Maintained Load Method as

specified in Section 9.4. 9.4 Pile Testing 9.4.1 General Unless otherwise specified, pile tests shall be carried out as described in this

Section of the Specification. 9.4.2 Test Load and Kentledge The test load shall be applied by means of an hydraulic jack of adequate

capacity fitted with measuring devices capable of registering loads in increments not exceeding 2 tons. The hydraulic jack and measuring devices shall be approved by the S.O. before use. Certificates of calibration for all measuring devices shall be provided at the S.O.'s request.

The kentledge shall be provided by a heavy mass of dead load, exceeding the

maximum test load required, supported centrally over the test pile on suitably constructed temporary staging or by means of anchor piles.

If anchor piles are used to provide reaction for the jack, these piles shall not

be closer to the test pile centre to centre than 1.5 metres or 5 pile diameters or equivalent whichever is the larger. Anchor piles, which later form part of the piled foundation to the structure, shall be appropriately re-driven to the required set or level as directed by the S.O. all to his full satisfaction.

9.4.3 Settlement Measurement Vertical movements of the test pile shall be measured by at least two dial

gauges, with a minimum of 25mm travel, graduated in 0.025mm divisions. The gauges shall be erected on stiff steel beams, the ends of which shall rest

on or be fixed to reliable supports. Such supports shall be located not closer than 1.8 metres from the test pile, and shall be rigidly fixed to the ground to a depth of not less than one metre of concrete surround. In addition, the elevation of the supports shall be checked frequently with reference to a fixed benchmark. The entire measuring assembly shall be properly protected


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against rain, direct sunlight and other disturbances that might affect its reliability. Temperature readings shall be taken when requested by the S.O.

9.4.4 Equipment and Personnel for Load Test All kentledge staging, anchor piles, equipment, shelter, supports, and the

like required for the load test shall be provided by the Contractor, who shall also provide all necessary facilities to enable the S.O. to check all readings during the progress of the test.

The S.O. will supervise and direct the whole process of the test and provide

skilled staff to assist in taking and recording all readings. The Contractor shall provide all other labour required for the proper

execution of the test, including the construction and dismantling of the load staging and handling of the kentledge materials on and off the load stage, and the like and for the continuous and competent watching of the whole assembly, all to the full satisfaction of the S.O.

9.4.5 Procedure of Testing The MAINTAINED LOAD method of testing shall be carried out on the test

pile. The S.O. may at his discretion decide to carry out the CONSTANT RATE OF PENETRATION method of testing on completion of the Maintained Load Test.

a) Maintained load test

The load shall be applied in increments of 25% of the working load until a maximum test load of twice the working load is reached. Each increment of load shall be applied as smoothly and as expeditiously as possible. Settlement readings and time observations shall be taken before and after each new load increment.

A settlement-time graph shall be plotted to indicate when the rate of settlement of 0.05mm in 15 minutes is reached. A further increment of load shall be applied when this rate of settlement is achieved or until a minimum time of 2 hours elapsed, whichever is later. The process is repeated until the maximum test load is reached. The maximum test load shall than be maintained for a minimum of 24 hours, and time-settlement readings shall be taken in regular intervals as for the other load stages. The test load shall then be decreased in four equal stages and time-settlement readings taken as described aforesaid until the movement ceases. At least 60 minute intervals shall be allowed between the unloading decrements.

b) Constant rate of penetration test

The load shall be applied at a constant rate of penetration of a value varying between 0.75mm per minute to 1.5mm per minute, the rate to be so chosen as to suit the available pumping equipment. Both settlement and time readings shall be recorded every minute. Further loading shall


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be discounted when the loading varies directly as the penetration in the case of end-bearing piles in sand or gravel or when the rate of penetration is constant without further increase in the load in the case of friction piles in clay. Loading shall then be released gradually and rebound readings taken.

9.4.6 Records of Test The Contractor shall submit two copies of all records of results, not

including the original copy, together with load-settlement and load-time graphs to the S.O. on completion of each test.

9.4.7 Interpretation of Test Results The S.O.'s interpretation and conclusions arrived at on the test results shall

be final. When the pile test as prescribed has been carried out, the pile so tested shall be deemed to have failed if:-

a) The residual settlement after removal of the test load exceeds 6mm, b) The total settlement under Design Load exceeds 13mm, c) The total settlement under twice the Design Load exceeds 38mm. 9.5 Measurement of Piles and Piling Piles and piling and all works in connection therewith shall be valued by

measurement of only such items as are provided in the Bills of Quantities. The supply and delivery of precast reinforced concrete, and pretensioned

spun concrete piles shall be measured in accordance with the total length of piles incorporated in the permanent works. Piles delivered to the Site and cut piles not incorporated in the Works shall on completion of piling be removed from the Site and no payment of any kind shall be due to the Contractor for such piles.

The site handling, transporting and pitching of extension piles shall be in

accordance with the total number of pile lengths handled whether they be full length piles or cut lengths from standard pile lengths.

Pile driving shall be measured by the total length of penetration obtained

below formation, river or stream bed level, as appropriate and approved by the S.O. No distinction shall be made between the driving of a standard length of pile and the driving of an extended pile.

Payment of the following items shall be measured once only for each pile

location irrespective of the actual numbers of items eg. end-plates, joints, etc.

a) Mild steel end plates and splicing bars to be welded to end plates. b) Haul, handle, pitch to position ready for driving pile and extension pile. c) Jointing pile and pile extension including painting with coal tar epoxy.


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The respective lengths of any pile subsequently withdrawn and remedial work executed to correct defective piles shall not be measured for payment.

Bakau piles and timber piles shall be measured only by the total length of piles supplied, delivered and driven below the foundations to the level of the pile cut-offs.

Steel sheet pile items shall be measured on the basis of the overall plane area

and the shape of the sheet piles will not be considered in measurement.

The Contract Rates for piles and piling shall include for the full cost of providing temporary staging and all equipment, labour and materials necessary for transporting, handling, pitching, driving, removing or re-driving (if incorrectly driven or damaged), measuring and recording pile set and keeping field records, idle time, all in compliance with the requirements of the Specification. Separate items are provided for load tests, raking piles, shoes for steel pipe and timber piles, jointing of piles and cutting of pile heads after driving.


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SECTION 10.0 – ROADWORKS



10.0 ROADWORKS 10.1 Preparation of Formation to Receive Road

The preparation of formation shall be carried out only after completion of all sub-grade drainage, piped drains, services and ducts or any other drainage work that might affect the works, unless otherwise agreed by the S.O., and such preparation shall be carried out immediately prior to the laying of the sub-base or the road-base where no sub-base is required.

The surface of the formation shall be substantially uniform in density throughout its entire width and shall conform to the density requirements for compaction. It shall be trimmed to conform to the lines, camber, grades and typical cross sections shown on the Drawings, or as directed by the S.O. The surface shall be constructed to sufficient accuracy to permit the construction of subsequent layers of material to the thickness, cross-section surface tolerance and compaction specified but in no case shall a tolerance of + 25mm from the levels shown on the Drawing be permitted. Where ruts or other objectionable irregularities occur as a result of construction traffic or other causes, the Contractor shall reshape and re-compact the formation to the required density before the sub-base or base is placed.

10.2 Earth Subgrade

Where soft spots and unsuitable material occur, they shall be removed and backfilled with approved stable material and compacted according to the Specification in Table 10.1, "Plant and Method Specification for Compaction of Earthworks and Subgrades". The formation shall then be checked and the final trimmed surface shall be rolled by one pass of a smooth-wheeled roller of not less than 5 tonnes or an equivalent vibratory roller prior to the laying of the sub-base or base-course.

Notwithstanding the above the top 300mm of the finished embankment shall be compacted to a dry density equal to at least 95% of the maximum dry density as determined by BS 1377:1975, Test No.13. Other layer of sub base and shoulder shall be compacted to a dry density equal to at least 90% of the maximum dry density as determined by BS 1377:1975, Test No.13.

The formation shall be so constructed to drain surface water to the side ditches or other drainage system. If the Contractor allows the moisture content of the completed formation to reach a value above the permitted maximum for the compacted material, the Contractor shall allow the materials to revert to an acceptable moisture content and, if directed by the S.O., make good at his own expense the surface by recompaction before laying the sub-base or base.

10.3 Subgrade of Rock

Where the surface of an excavation in rock has deteriorated and is no longer acceptable as subgrade, the Contractor shall remove all loose rock and replace it with suitable approved material.


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10.4 Pavement Thickness

The thickness of the various layers of the pavement shall be as shown on the Drawings. However before the construction of the pavement the S.O. may carry out or direct the Contractor to carry out California Bearing Ratio (C.B.R.), soaked or unsoaked tests as described in BS 1377 on the prepared subgrade to determine the strength of the subgrade.

The S.O. may order variations in the thickness of the various layers of the pavement as shown in the typical cross-section Drawings as a result of the above tests. Any such changes shall be treated as a variation to the Contract.

10.5 Sub-base Materials

The sub-base material shall be hard, durable and clean. It shall be granular material such as laterite or gravel or crushed rock or sand and shall be free from organic material, clay balls and any other deleterious substances. The laterite or crushed rock or gravel shall conform to one of the following gradings :-

Percentage By Weight Passing

BS Sieve Size (A) (B)

40 mm 25 mm 20 mm 10 mm 5 mm

2.4 mm 420 microns 75 microns

100

75 - 100 60 - 90 45 - 75 30 - 60 20 - 50 10 - 30 0 - 2

-

100 70 - 100 58 - 75 35 - 65 25 - 50 15 - 30 0 - 2

The sand shall conform to the gradings given below :-

BS Sieve Size


10 mm 5 mm


100

95 - 100 45 - 80 10 - 30 2 - 10


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10.6 Alternative Sub-base

Alternative suitable material may be accepted subject to the prior approval of the S.O. The proposed sub-base material shall have a laboratory controlled unsoaked CBR value not less than 30% when compacted to 95% of maximum dry density as determined by the BS 1377:1975 Test No 13 or modified AASHO compaction test. The material shall be free from vegetable matter, soft particles or clay lumps and shall conform to one of the following gradings:-


BS Sieve Size (A)

(B)

40 mm 20 mm 10 mm 5 mm


100

80 - 100 55 - 90 40 - 70 12 - 55 12 - 30 5 - 20

-

100 80 - 100 55 - 90 40 - 70 20 - 40 8 - 25

The portion passing the No.36 sieve shall, if it is plastic, have a liquid limit not greater than 35 and a plasticity index not greater than 11.

10.7 Compaction of Sub-base

The sub-base material shall be laid in layers not exceeding 225 mm in thickness. At the time of laying and compaction of sub-base, the formation shall be dry. Compaction of sub-base shall be carried out by adequate compaction equipment approved by the S.O. Rolling operations shall begin from the outer edge towards the centre gradually in a longitudinal direction except on superelevated curves where rolling shall begin at the low side and progress towards the high side. Sub-base sandy material shall be compacted by use of vibrating equipment. Each layer shall be compacted to at least 95% of the maximum dry density as determined by BS 1377:1975, Test No. 13. If necessary the Contractor shall add water to the sub-base material to achieve the required moisture content. Sub-base material containing excess moisture shall be dried by harrowing, scarifying, typing, ripping or mixing prior to or during compaction. The Contractor shall ensure that the subgrade is not disturbed by the operations carried out to adjust the moisture content of the sub-bases material.


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The finished sub-base shall not vary more than + 20 mm from the grade or level shown on the Drawing. The thickness of the finished sub-base shall be on average not less than the required thickness.

10.8 Road-base Materials

The crushed rock road base to be placed on top of the sub-base shall consist of sound durable material free from clay lumps, organic matter, objectionable coatings or other foreign matter. It shall be laid to give a total compacted thickness, width, grade and levels as shown on the Drawings or as directed by the S.O. It shall be from a quarry approved by the S.O.

The material shall be crushed rock of hard durable particles or rock crushed to the correct size, well graded and lie within the following grading limits: -

BS Sieve Size


50 mm 40 mm 20 mm 10 mm 5 mm


100

95 - 100 60 - 80 40 - 60 25 - 40 15 - 30 8 - 22 0 - 8

Note: 1. The particle size shall be determined in accordance with the

requirements of BS 1377. 2. The material passing No.36 BS Sieve when tested in accordance with

BS1377 shall be non-plastic.

It shall have a CBR value of not less than 80 when compacted to 95% of the maximum dry density as determined by BS 1377:1975 Test No.13. The flakiness index of the coarse aggregate shall be less than 35 per cent.

10.9 Laying and Compaction of Roadbase

All work on the portion of the subgrade or sub-base on which the roadbase is to be laid shall be properly shaped and compacted in accordance with the requirements of the Specification before the placing of the roadbase material on that portion. The preparation of the subgrade or sub-base shall be completed at least 200 metres ahead of the placing of the roadbase material. The roadbase shall be constructed to the full compacted thickness as shown on the Drawing, or as directed by the S.O. All material shall be placed and spread evenly to the full width of the roadbase. The maximum compacted thickness of any one layer shall not exceed 150mm.


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When the specified compacted thickness of roadbase exceeds 150mm, the base shall be constructed in two or more layers of approximately equal thickness. Each layer shall be compacted to the required density before the next layer is placed. Care shall be taken to prevent segregation of the material into the coarse and fine fractions. Segregated surface areas of a base constructed or base material contaminated to such an extent that it no longer complies with the Specification shall be removed and replaced with well graded and satisfactory material at the expense of the Contractor. The material shall be spread by a motor grader or any other approved mechanical plant. Tipping of aggregate and laterally spreading by dozer or motor grader can cause segregation between the coarse and fine particles, which results in hungry patches during compaction. Should this occur, all such areas shall be scarified and additional fines added before recompaction, at the Contractor's own expense.

When a roadbase is spread adjacent to concrete kerbs or gutter sections, extreme care shall be exercised so as not to damage the kerbs or gutters. Any damaged kerbs or gutters shall be removed and replaced at the Contractor's own expense. Compaction shall be completed as soon as possible after each layer has been spread and shaped satisfactorily. Each layer shall be thoroughly compacted with suitable compaction equipment to the requirement specified in Table 10.2, "Compaction Procedure for Unbound Sub-base and Roadbase Materials and for Soil-Cement and Cement-bound Granular Roadbase" and to a compacted density of at least 98% of the maximum dry density as determined in accordance with BS 1377:1975. Rolling operations shall begin along the edges and progress towards the centre gradually in a longitudinal direction. On superelevated curves, the rolling shall begin at the low side and progress towards the high side. The rolling operation for each layer shall continue until all rolling marks, ridges or cracks are eliminated. Any irregularities, segregation or loose material which may develop in the surface during or after construction shall be corrected or removed and the defective areas made good to the full thickness of layer and recompacted. Special care shall be taken to obtain full compaction in the vicinity of both longitudinal and transverse joints. On completion of compaction the surface of any layer of material shall be well knitted, free from movement under compaction plant and from compaction planes, ridges, cracks or loose material. All loose segregated or otherwise defective areas shall be made good by being removed and replaced with properly graded material. Before the laying of each layer of roadbase material a partial width of the shoulder, not less than 300mm wide, shall be constructed to the top of each uncompacted layer of the base to act as a haunch to support the edges of the roadbase during rolling.


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The roadbase material shall be maintained at the correct moisture content as necessary for proper compaction. Moisture content control of the roadbase material shall be accomplished by sprinkling with water or drying as required, at the Contractor's own expense. The surface of the aggregate roadbase shall be well drained at all times.

10.10 Finished Surface

The finished roadbase surface shall be even, free from hungry patches, irregularities, loose material or fines and true to cross- section, lines and level. Any irregularities on the finished roadbase surface of more than 12mm when measured with a straight edge 3 metres long laid either parallel to the centre line of the road or laid transversely, shall be corrected by loosening, adding or removing material, reshaping and recompacting. The finished surface level of the roadbase shall not vary from the level shown in the Drawing by more than 12 mm.

10.11 Definition and Requirements Associated with Table 10.1

Number of passes is the number of times that each point on the surface of the layer being compacted has been traversed by the compaction plant. The effective width of a pneumatic tyred roller for this purpose is the sum of the widths of the individual wheeltracks together with the sum of the spacing between the wheeltracks, provided that each spacing does not exceed 288mm. When the spacing exceeds 288mm the effective widths shall be taken as the sum of the widths of the individual wheeltracks only.

The load per 10cm width is the total weight on the roller divided by the total roller width. Where a smooth-wheeled roller has more than one axle the machine will be assessed on the basis of the axle giving the highest value of load per 10cm width. Wheel load is the weight of the roller divided by the number of wheels. Vibratory rollers are self propelled or towed rollers having means of applying mechanical vibration to one or more rolls. (i) The requirements of vibratory rollers are based on the use of the lowest

gear on a self propelled machine and a towing speed of 1.5 - 2.5 km per hour for a towed machine. If higher gears or speeds are used, an increased number of passes shall be provided in proportion to the increase in speed of travel.

(ii) Vibratory rollers operating without their vibration mechanism in use

will be classified as smooth wheeled rollers. (iii) Vibratory rollers shall only be operated with their vibration mechanism

operating at the frequency of vibrating recommended by the manufacturers. All such rollers shall be equipped with a device automatically indicating the frequency at which the mechanism is operating.


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Combination of different types of plant will be permitted in which case the number of passes for each type shall follow such proportion of the appropriate number in Table 10.2 as will together produce the same total compactive effort as any type operated singly in accordance with Table 10.2.

10.12 General

This section specifies the methods of storage, handling, heating and the procedure to be used for testing the efficiency of the spraying equipment. Petroleum Bitumen shall comply with the requirements (for the appropriate grade) given in BS 3690. Petroleum Bitumen shall be intended when material is referred to as "Asphalt Cement" "Straight-run Bitumen", "Penetration grade bitumen", or by its penetration value (as for example 80 - 100 pen).

10.13 Cutback Bitumen

Cutback bitumen shall be of the rapid curing type or the medium curing type and shall comply with the requirements (for the appropriate grade of cut back bitumen) given in BS 3690.

10.14 Bitumen Emulsion

Bitumen Emulsion shall be of the anionic and or cationic type and shall comply with the requirements (for the appropriate grade) given in BS 434.

10.15 Storage, Handling and Heating-of Bitumen

Bituminous materials shall be handled and stored with due regard for safety and in such a way that at the time of use in the work the material conforms to the Specification. In particular, bitumen emulsion shall be handled with care and not subjected to mechanical shocks or extremes of temperature likely to cause separation of bitumen. Bitumen emulsion showing signs of separation shall not be used. Bitumen shall be heated in an approved type of bitumen heater having a capacity commensurate with the output required. The heater shall be fitted with a thermometer accurately registering the temperature of the bitumen and so situated as to be readily accessible. Great care must be ensured that the bitumen be heated to a temperature within the range specified for its grade. Overheated bitumen shall, if the S.O. so direct, be disposed off at the Contractor's expense.

10.16 Depot Tray Test

The Contractor shall provide a set of 50mm wide trough as described in Appendix "A" of BS 1707 and shall carry out Depot Tray Test A in the presence of the S.O. of the bitumen distributor in accordance with BS 1707.


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This test shall be carried out prior to using the distributor for the first time on the Contract and at such intervals thereafter as may be required by the S.O. Should the quantity of bitumen in any trough or troughs be found to lie outside the prescribed tolerance from the average, the Contractor shall carry out such adjustments to the distributor, or, including the replacement of any faulty jets, as may be necessary to achieve compliance with the test requirements.

10.17 Material

The prime coat shall be a medium curing cut-back bitumen of grade M.C.O. or M.C.I. The actual grade to be used shall determine the penetration of each grade. Material for blinding shall be clean, sharp and free from organic matter and with not more than 45% of material passing No.25 BS Sieve. Not more than 5% of material used for blinding shall be retained on the 6.35mm (1/4in.) BS Sieve. Alternatively, grit arising from the crushing of rock may be used, subject to the approval of the S.O. regarding its grading.

10.18 Surface Preparation

Immediately before the application of the prime coat the surface of the road base shall be brushed clean and free from all dust, dirt, dried or wet mud, organic matter or any other loose material to the satisfaction of the S.O. If considered necessary by the S.O., the surface of the road base shall be slightly damped before the application of the prime coat. Moisture control of the road base shall be carried out by the Contractor using a wetting agent and method approved by the S.O. and to a level of dampness to the satisfaction of the S.O. Preparation of the surface as above shall not precede the application of bitumen by more than 450m. Should any part or parts of the prepared surface become contaminated or unsuitable for the application of the prime coat, due to lack of care on the Contractor's part to protect the surface or due to prolonged exposure, the surface shall be restored or reprepared to the satisfaction of the S.O.

10.19 Application of Prime Coat

The prime coat shall be applied uniformly over the full width of the prepared road base by means of an approved pressure load mobile distributor complying with the requirement of BS 1707. In addition to the Special Requirements detailed in Section 3 of BS 1707, the pressure feed mobile distributor shall be fitted with a spray bar through which the hot bitumen can be circulated while the distributor is not spraying. The jets shall be so arranged in the spray bar that they are effectively preheated in the same


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temperature as the circulating bitumen. The bitumen shall be applied at a temperature in accordance with the table below and at the rate of spray as directed by or agreed with the S.O. after carrying out Site tests, but not to be less than 440ml/sq.m.

SPRAYING TEMPERATURE FOR BITUMEN PRIME COAT

TEMPERATION OF APPLICATION

GRADE OF BITUMEN F DEGREES

C DEGREES

M.C.O. M.C.I.

100 - 135 135 - 160

40 - 60 60 - 70

10.20 Spraying Procedure

Immediately before any spraying run is begun the spray bar shall be tested by allowing all the jets to discharge simultaneously for about half a minute with a slotted metal tray placed beneath the spray bar whilst a visual inspection is made. Any jet which is seen not delivering a uniform spray cone shall be cleaned or replaced. After testing the spray bar the distributor shall proceed with the spraying run without delay. Any areas insufficiently covered shall be resprayed by spray lance to the satisfaction of the S.O. No spraying of bitumen shall be carried out during, or when rain is imminent, or immediately after rain until the road base has dried. After spraying the surface shall be left for a minimum period of three (3) hours before blinding. Blinding shall be applied so as to obtain a uniform covering without evidence of bare or fat patches of bitumen. The blinding shall be rolled with not more than two passes of an approved roller.

10.21 Protection of Prime Coat

After laying the prime coat, barriers shall be erected to keep the area surfaced free from traffic for such period as the S.O. may direct.

10.22 Aggregate, Binder and Composition

This is a general specification for bitumen macadam road pavement surfacing. The base course and wearing course shall have thickness as shown on the Drawings and laid in accordance with BS 4987 : 1973 after construction of road base and bitumen prime coat or tack coat. Coarse Aggregate


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The coarse aggregate shall be natural aggregate sub-stantially free from the material passing a BS 3.35mm (1/8in) Sieve. It shall be hard, clean, durable


crushed rock of the granite or limestone group or of any other rock group as may be approved by the S.O. Only granite shall be used for the wearing course.

Fine Aggregate i) The fine aggregate shall consist of crushed rock or of clean sand,

substantially all of which shall pass a 3.35mm (1/8 in.) BS Sieve. If sand is used, the content of silt, loam and clay shall not exceed 3 per cent by weight of the fine aggregate, determined in accordance with BS812, method A or B.

ii) If added filler is used in the bitumen macadam, it shall consist of

crushed rock, hydrated lime, Portland cement; or other material approved by the S.O. At least 75 per cent of it shall pass a 75 um (No.200) BS Sieve.

Binder The binder shall be straight run bitumen, which shall have a penetration at 25 deg C, between 80 and 100. Composition of Mixtures The composition of freshly mixed material for the bitumen macadam shall comply on analysis with the following requirements: - a) Base Course

Passing BS Sieve (mm) 1 ½" (38mm)

Nominal Size Aggregate % By Weight

63 50 40 25 13 3

Binder Content as found by analysis

- 100

90 - 100 50 - 80 10 - 30 0 - 10

3.0 - 3.8


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b) Wearing Course

Passing BS Sieve (mm)

3/4" (20mm)

Nominal Size Aggregate

25 20 13 10 6 3

1.2 0.075

Binder Content as found

by analysis

100

95 - 100 70 - 90 55 - 75 40 - 60 25 - 40 14 - 30 3 - 6

4.4 - 5.4

Note:

a) When gravel other than limestone gravel is the aggregate, the material passing 75 micron BS test sieve shall include portland cement or hydrated lime to the amount of 2% by mass of the total aggregate.

b) The exact bitumen content depending on density, shape and grading

of the aggregate will be determined by the S.O. 10.23 Mixing

The aggregate shall be surface dried, and the aggregate and binder separately heated to the following temperatures before entering the mixer: - Aggregate 120 - 148 deg C Binder 130 - 162 deg C It is particularly important to avoid excessive heating of the binder, and excessively high temperatures of the aggregate at the time of mixing, as these will adversely affect the quality of the resultant macadam. The materials, including any added filler, shall be weighed or measured in a mechanical mixer and thoroughly mixed in such a manner that all particles of the aggregates are completely and uniformly coated. The mixing plant shall have a capacity sufficient to supply the paver on the road continuously when spreading the mix at normal speed and required thickness.


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10.24 Transport

The bitumen macadam shall be transported from the manufacturing plant to the Site in clean vehicles and shall be protected against adverse weather conditions by means of tarpaulins. The use of coated dust, oil or water on the interior of vehicles to facilities discharge of the bitumen macadam may be permitted, but the amount shall be kept to a minimum and any excess shall be removed by tipping or brushing. It is particularly important that bitumen macadam, which is to be laid warm, shall be protected to minimise loss of heat during transit so that all material is delivered in a condition suitable for spreading and compacting. The temperature of the Bitumen Macadam, during delivery to laying site, shall be between 104oC and 132oC and at the time of rolling not less than 79oC.

10.25 Sampling and Testing

Sampling and testing of the aggregate and mixed materials carried out shall be in accordance with the following British Standards as appropriate: - a) BS 812 - Methods for the sampling and testing of mineral

aggregates, sand and fillers. b) BS 598 - Sampling and examination of bituminous mixtures

for roads and buildings. c) BS 3235 - Test methods for bitumen.

10.26 Bitumen Macadam Layer Thickness and Tolerance

The base course and wearing course shall be laid by machine in single course each and the compacted thickness of the individual courses shall be:- Base course : 65mm Wearing course : 35mm The accuracy of finish in the longitudinal direction shall be determined by measuring the gap under a 3m straightedge, placed in any position on the road surface parallel to the centre line; the gap at any place between the points at which the straightedge is in contact with the road shall not exceed the following limits:- Base course : 10mm Wearing course : 6mm The transverse profile shall conform to a similar standard of accuracy, using a correctly shaped template instead of a straightedge.


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10.27 Laying of Bitumen Macadam

The bitumen macadam shall be laid by machine. Works shall not proceed under unsuitable weather conditions. The machine shall be of a type preferably self-propelled and capable of laying bitumen macadam continuously so as to produce automatically an even, smooth and compact surface to the required widths, thickness and cross-falls without segregation of the bitumen macadam. A fully trained and experienced operator shall be in direct charge of the machine. The bitumen macadam shall be supplied continuously to the machine. Material supplied to the machine shall be laid as soon as possible after delivery. The machine shall be used only when it is in a serviceable condition. Bituminous material remaining in the hoppers, conveying and spreading mechanisms, tempers and screeds, shall be cleaned off at the end of each working day. On no account shall cleaning solvent be allowed to come into contact with any road surfacing material. Accumulations of material not of the specified quality shall be removed from the Site. The machine shall be operated to avoid, as far as possible, dragging of the bitumen macadam. On carriageways, narrow strips remaining alongside machine work shall be as far as possible hand laid and rolled at the same time as the machine laid work and allowance shall be made for extra compaction of hand laid strips. Continuous inspection of the finished surface as it is laid shall be carried out and any defects immediately rectified before any rolling takes place.

10.28 Bituminous Tack Coat

The surface of the dense bitumen macadam base course shall be cleaned immediately prior to the application of the tack coat. The bituminous material shall be applied by means of distributor at the rates directed by the S.O., but not to be less than 270 ml/sq.m. and at temperatures within the range required.

10.29 Joints

When a transverse construction joint is to be made, the material shall be cut back to a vertical face of the full depth of the course being laid and painted with bitumen or bitumen emulsion before any new material is laid. On longitudinal joints a complete bond of the two strips after compaction shall be ensured. If this is not possible, the edge shall be cut back and painted as above.


124


10.30 Laying Around Manhole Covers

When laying around manhole covers and similar fittings, those parts against which the bitumen macadam is to abut shall be cleaned and painted with bitumen or bitumen emulsion prior to laying operations. The bitumen macadam shall be tamped so that after final compaction, the finished surface is level with, or slightly proud of, such fittings.

10.31 Compaction

As soon as rolling can be effected without causing undue displacement, the bitumen macadam shall be uniformly compacted by rolling to a density of not less than 98 percent of the Marshall Density of the mix. Compaction shall be carried out with a roller or rollers of weight not less than 6 tons nor exceed 10 tons, and the width of a roller shall not be less than 1.0m. The bitumen macadam shall be rolled in a longitudinal direction, working from the sides to the centre of the carriageway, overlapping on successive passes by at least one half of the width of the rear roll. The roller shall be fitted with a quick reverse and smooth acting clutch. Rollers shall not be allowed to stand on newly laid macadam while there is a risk that the surface will be deformed thereby. Traffic shall not be allowed to pass over the surface until the bitumen macadam has been completed and is adequately set.

10.32 Road Shoulders

Road shoulders shall be constructed to the lines, grades, levels, dimensions and cross sections shown on the Drawings and as directed by the S.O. The shoulder shall be constructed on a previously prepared sub-base or subgrade finished as required in the Specification. The work shall be carried out in conformity with the requirements for simultaneous construction of sub-base or base where required and as approved by the S.O. The material for shoulder construction shall be of well-graded laterite, gravel mining ballast or other suitable local material approved by the S.O. and conforms to the requirements of sub-base material and the following additional requirements: Minimum Plasticity Index : 10 Maximum Plasticity Index : 30 (Above for material passing 425 per sieve) Minimum CBR at 95% maximum dry density : 20 Shoulders shall be placed and compacted in layers not exceeding 200mm thickness before compaction. The layers shall be compacted to 95% of maximum dry density as determined in accordance with BS 1377:1975.


125


10.33 Shoulder Base Selected Fill Grading

The selected fill material is to be used as shoulder base material over the compacted subgrade at the edge of the pavement and the verge and any other areas shown on the Drawings or as directed by the S.O. It shall comprise of clean, hard, durable, well-graded sandy gravels obtained from crushed rock and shall be free from any organic matter or deleterious material. The grading of the material shall fall within the following limits: -

BS Sieve (mm)

% Passing By Weight

50 40 20 10 5

2.4 600 microns 75 microns

100 80 - 100 45 - 70 25 - 50 15 - 30 12 - 20 6 - 12 2 - 8

Alternative suitably graded material may be accepted by the S.O. or used as directed by the S.O.

10.34 Lateral Shoulder Sub-drains

Shoulder sub-drains shall be constructed along the road shoulders as shown on the Drawings or as directed by the S.O. Such lateral shoulder sub-drains shall be constructed of graded selected fill to provide free drainage outlet from the pavement sub-base and shall be constructed to the dimensions and material as shown on the Drawing or as directed by the S.O.

10.35 Refilling of Excavated Pipe Trenches for Roadways

In roads and in all other places where the S.O. considers mechanical compaction is required, the suitable material above the pipe shall be spread in layers of not greater than 150 mm and thoroughly consolidated by mechanical means as listed out in Table 10.2. As soon as the compaction of sub-base is completed the roadbase will be laid and compacted, before proceeding with the laying of the premix. Any depressions found shall be made up with material of the same kind as that of the original surface all at the Contractor's own expense.

10.36 Notes Relating to Table 10.1

The notes given in this Clause and Tables 10.1 and 10.2 are for guidance only and shall not relieve the Contractor from his basic obligation to produce work to the required standard of the Specification.


126


i) The depth of compacted layer is the height by which an embankment is raised by each successive compacted layer.

ii) Number of passes is the number of times that each point on the

surface of the layer being compacted has been traversed by the item of compaction plant. In assessing the number of passes of pneumatic tyred rollers to meet the requirements of Table 10.1 the effective width shall be the sum of the widths of the individual wheel tracks together with the sum of spacing between the wheel tracks provided each spacing does not exceed 225mm. The effective width shall be the sum of the widths of the individual wheel tracks when the spacing exceeds 225mm.

iii) The forces per 100mm width is the total force (weight) on the roll

divided by the total roll width. Where a smooth-wheeled roller has more than one axle the machine will be assessed on the basis of the axle giving the highest value of force per 100mm width.

iv) For pneumatic tyred rollers, wheel load is the total weight of the roller

divided by the number of wheels. v) Vibratory rollers are self-propelled or towed having means of applying

mechanical vibration to one or more rolls.

a) The requirement for vibratory rollers are based on the use of the lowest gear on a self-propelled machine and a towed machine. If higher gears or speeds are used an increased number of passes shall be provided in proportion to the increase in speed of travel.

b) Vibratory rollers operating without their vibration mechanism in use will be classified as smooth-wheeled rollers.

c) Vibratory rollers shall be operated with their vibration

mechanism operating only at the frequency of vibration recommended by the manufacturers. All such rollers shall be equipped with a device automatically indicating the frequency at which the mechanism is operating.

vi) Vibrating-plate compactors are machines having a base-plate to which

is attached a source of vibration consisting of one or two eccentrically-weighted shafts.

a) The static pressure under the plate of a vibrating-plate

compactor is calculated by dividing the total weight of the machine in working order by the area in contact with compacted soil.

b) Vibrating-plate compactors shall be operated at the frequency

of vibration recommended by the manufacturers. They shall normally be operated at travelling speeds of less than 15 m/min but if higher speeds are necessary the number of passes shall be increased in proportion to the increase in speed of travel.


127


vii) Vibro-tampers are machines in which an engine-driven recipro- cating mechanism acts on a spring system, through which oscillations are set up in a base-plate.

viii) Power rammers are machines, which are actuated by explosions in an

internal combustion cylinder, each explosion being controlled manually by the operator.

In the case of power rammers one pass will be considered as made when the compacting shoe has made one strike on the area in question.

ix) For items marked with an asterisk the rollers shall be towed by

track-laying tractors. Self-propelled rollers are unsuitable. x) Where combinations of different types or categories of plant are used,

the compaction requirements shall be: - a) the depth of layer shall be that for the type of plant requiring

the least depth of layer; and b) the number of passes shall be that for the type of plant

requiring the greatest number of passes. However, where the Contractor uses a lighter type of plant to provide some preliminary compaction only these requirements to assess the effective compaction could be disregarded.

10.37 Geotextile Filter Membrane

The geotextile to be used, where specified or shown on the Drawings, for the rock filled gabion/mattresses and road sub-base/formation interface shall conform to the following specifications: -

Criteria

I) Gabion/Mattresses

Minimum Value

II) Roadwork

Minimum Value Tensile strength Maximum force sustained in grab tension with 45% elongation (200 mm strip) CBR puncture resistance Minimum flow through geotextile under 100 mm head of water Maximum pore size Acid resistance Basic (alkali) resistance Coefficient of variation

7.7 kN/m 0.68 kN 1.3 kN 50 l.p.s./sq metre 160 µm (max.) pH>=2 pH<=13 10% (max.)

20 kN/m - 3.3 kN 13 l.p.s./sq.metre 145 µm (max.) pH>=2 pH<=13 10% (max.)


128


The geotextile for road sub-base formation shall be woven type material. The geotextile for rock filled gabion/mattresses can be non-woven type. The geotextile material shall be resistant to general chemical attack, oil, petrol, petroleum bitumen, cut back bitumen, bacteria, fungi and the like. Additionally, the geotextile material shall not deteriorate significantly in strength due to exposure to sunlight. The geotextile material shall retain at least 80% of its original strength after an exposure to 10,000 Langley's isolator radiation.

10.38 Storage of Geotextile Filter Membrane

The geotextile material shall be stored according to the manufacturer's recommendation out of sunlight. The opaque wrapping/packaging around the geotextile shall not be removed until immediately before use. Any geotextile material deemed by the S.O. to be in damaged or deteriorated condition shall be replaced by the Contractor at his own cost.

10.39 Laying and spreading over the Geotextile Filter Membrane

The geotextile shall be laid on trimmed formation, or compacted embankment bench level, prior to laying of the sub-base or drainage blanket material. Following this, the sub-base or drainage blanket material shall be uniformly tipped onto the geotextile filter membrane. The thickness of the layer immediately on top of the geotextile shall not be less than 250 mm and not greater than 400 mm, or as directed by the S.O. Any tear, puncture or damage to the geotextile shall be made good by patching with 500 mm minimum overlap, by the Contractor at this own cost, to the satisfaction of the S.O. The as laid geotextile material shall not be left uncovered and exposed to sunlight for a period greater than six hours. The S.O. may reject all such material left exposed to sunlight for more than six hours on the grounds of deterioration due to over-exposure to sunlight.


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225 250

Unsuitable

TABLE 10.1 PLANT AND METHOD SPECIFICATION FOR COMPACTION OF EARTHWORKS AND SUB-GRADES

Cohesive Soil

Well-Graded Granular &

Dry Cohesive Soil

Uniformly-Graded Materials

TYPE OF COMPACTION

PLANT

CATEGORY

Maximum Depth Of

Compacted Layer (mm)

Minimum Number Of

Passes

Maximum Depth Of


Minimum Number Of

Passes

Maximum Depth Of


Minimum Number Of

Passes

Smooth-Wheeled Roller

Force Per 100mm Width (kN)

2.1 - 2.6 2.61 - 5.2

more than 5.2

125 125 150

8 6 4

125 125 150

10 8 8

125 125

Unsuitable

10* 8*

Unsuitable Grid Roller

Force Per 100mm Width

(kN) 2.6 - 5.2 5.3 - 7.8

more than 7.8

150 150 150

10 8 4

Unsuitable 125 150

Unsuitable 12 12

150 Unsuitable Unsuitable

10 Unsuitable Unsuitable

Vibratory Roller

Force Per 100mm

Width (kN)

0.25 - 0.45 0.46 - 0.70 0.71 - 1.25 1.26 - 1.75 1.76 - 2.3 2.31 - 2.8 2.81 - 3.5 3.51 - 4.2 4.21 - 4.9

Unsuitable Unsuitable

100 125 150 175 200

Unsuitable 12 8 4 4 4 4 4

75 75 125 150 150 175 200 225 250

16 12 12 8 4 4 4 4 4

150 150 150 200 225 250 275 300 300

16 12 6

10* 12* 10* 8* 8* 6*

* These rollers shall be towed. Self-propelled rollers are unsuitable.


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Cohesive Soil

heel Load onnes)

1.0 - 1.5

Unsuitable

8

Static

17.2 - 20.7

100 (4)

100 (4)

Table 10.1 (contd.)

Well-Graded Granular &

Dry Cohesive Soil

Uniformly-Graded Materials TYPE OF

COMPACTION PLANT

CATEGORY

Maximum Depth Of


Minimum

Number Of Passes

Maximum Depth Of


Minimum Number Of

Passes

Maximum Depth Of


Minimum Number Of

Passes

Pneumatic-tyred Roller

1.5 - 2.0 2.0 - 2.5 2.5 - 4.0 4.0 - 6.0 6.0 - 8.0 8.0 - 12.0 more than 12

125 150 175 225 300 350 400 450

6 5 4 4 4 4 4 4

Unsuitable Unsuitable 125 125 125 150 150 175

Unsuitable 12 10 10

8 6

150 Unsuitable Unsuitable Unsuitable Unsuitable Unsuitable Unsuitable Unsuitable

10* Unsuitable Unsuitable Unsuitable Unsuitable Unsuitable Unsuitable Unsuitable

Vibrating-plate Compactor

Pressure under

Base Plate(kN/m ) 2

8.6 - 10.3 10.3 - 12.1 12.1 - 13.8 13.8 - 17.2

more than 20.7

Unsuitable Unsuitable Unsuitable

100 (4) 150 (6) 200 (8)

Unsuitable Unsuitable Unsuitable 6 6 6

Unsuitable 75 (3) 75 (3) 125 (5) 150 (6) 200 (8)

Unsuitable 10 6 6 5 5

75 (3) 100 (4) 150 (6) 150 (6) 200 (8) 250 (10)

6 6 6 4 4 4

Vibro-tamper

(kg) 50 - 65 65 - 75 5 more than 75

150 (6) 200 (8)

3 3 3

125 (5) 150 (6)

3 3 3

150 (6) 200 (8) 225 (9)

3 3

W (T

Mass

3

* These rollers shall be towed. Self-propelled rollers are unsuitable.


131


Cohesive Soil Well-Graded Granular &

Uniformly-Grade

Minimum Number Of

Maximum Minimum Number Of Passes

Maximum Depth Of Compacted Layer (mm)

150 (6)

4

150 (6)

6 12

Table 10.1. (contd.)

Dry Cohesive Soil

TYPE OF

Minimum Number Of Passes

COMPACTION PLANT

CATEGORY Maximum Depth Of Compacted Layer (mm)

Passes

Depth Of Compacted Layer (mm)

Mass (kg)

more than 500

275 (11)

8

275 (11)



d Materials

Power Rammer

100


132


2.6 - 5.2 Unsuitable

12

8 Unsuitable

TABLE 10.2 COMPACTION PROCEDURE FOR UNBOUND SUB-BASE AND ROAD BASE MATERIALS AND FOR SOIL-CEMENT AND CEMENT-BOUND GRANULAR ROAD BASE

MINIMUM NUMBER OF PASSES TYPE OF

COMPACTION PLANT CATEGORY

< 110mm LAYER

< 150mm LAYER

< 225mm LAYER

Smooth-wheeled Roller

Force Per 100 mm Width (kN) > 5.2

16 8

16


Pneumatic-tyred Roller

Wheel Load (Tonnes) 4 - 6 6 - 8 8 - 12 > 12

12 10 8

Unsuitable Unsuitable 16 12

Unsuitable Unsuitable Unsuitable Unsuitable

Vibratory Roller

Static Force Per 100mm Width (kN) 0.71 - 1.25 1.26 - 1.75 1.76 - 2.3 2.31 - 2.8 2.81 - 3.5 3.51 - 4.2 4.21 - 4.9

16 6 4 3 3 3 2

Unsuitable 16 6 5 5 4 4

Unsuitable Unsuitable 10 9 8 7 6

Vibrating-plate Compactor

Static Force Under Base Plate (kN/m2) 13.8 - 17.2 17.2 - 20.7 > 20.7

5 3

8 6

Unsuitable Unsuitable 10


133


50 - 60

75

4

(kg)

8

Unsuitable

Table 10.2 (contd.)

MINIMUM NUMBER OF PASSES

TYPE OF COMPACTION PLANT

CATEGORY < 110mm LAYER

< 150mm LAYER < 225mm LAYER

Vibro-tamper

Mass (kg) 65 - 75 >

3 2

8 6 4

Unsuitable 10 8

Power Rammer on Dropping Weight Compactor

100 - 500 > 500

5 5

8

12

Mass


134


Laterite pavement shall be constructed and installed true to line, grade and crossfall as shown on the Drawings or as directed by the S.O.

The Contractor shall pay all necessary fees, fax or royalty to the relevant Authorities for the use of laterite from the borrow area and is deemed to be included in the Contract Rate.

10.40 LATERITE PAVEMENT 10.40.1 Preparation of Formation to Receive Road Pavement

The preparation of formation shall be carried out only after completion of all subgrade, drainage, pipe drains, services and ducts or any other drainage work that might affect the work unless otherwise agreed by the S.O. and such preparation of formation shall be carried out immediately prior to the laying of the laterite pavement. The surface of the formation shall be substantially uniform in density throughout the entire width and shall confirm to the density requirements for compaction. It shall be trimmed to confirm to the lines, chambers, grades and typical cross-section as shown in the Drawings or as directed by the S.O. A rough compensation maximum deviation of ± 25mm will be permitted of the surface on the final completed formation.

The Works Contractor shall ensure that till is compacted with a slight outward slope to ensure good run-off surface water.

10.40.2 Pavement Material

The Contractor shall submit sample of laterite for testing from his borrow area and approval obtained from the S.O. before construction of the laterite pavement. The laterite supplied for incorporation in the works shall be from the same borrow area from which the approved sample was obtained. Notwithstanding the laterite from the approved borrow area, the S.O. may reject any laterite for incorporation in the Works if in his opinion the material does not conform to the approved sample or unsuitable for the Works. The S.O.’s decision is final and not subject to arbitration. The cost and expense to remove any rejected material is deemed to be included in the Contract Rate.

The pavement shall consist of laterite, or other suitable local material approved by S.O. and compacted to a minimum thickness of 150mm or as directed by the S.O. The material shall be free from vegetable matter, soft particles, clay lumps; any organic matter or other deleterious substance and shall conform to one of the grading given below:


135


B.S. Sieve Percentage by Weight Passing

A

40mm 80-100 55-90 80-100

2.4 mm

75 micron 8-25

B

100 -

20 mm 100 10 mm 5 mm 40-70 55-90

30-55 40-70 420 micron 12-30 20-40

5-20

The portion passing No. 36 – B.S. Sieve shall, if it is plastic, have a liquid limit not greater than 35 and plasticity index not greater than 11.

Before construction of the laterite pavement, California Bearing Ratio (CBR) Soaked Test as described in B.S. 1377:1975 may be carried out on samples of the laterite materials and on the prepared laterite pavement by the S.O. The Contractor shall provide the attendance to carry out the test and the cost and expenses arising therefrom is deemed to be included in the Contract Rate.

10.40.3 Spreading and Laying the Laterite Pavement

The material shall be laid in one layer and compacted to thickness as specified with suitable and adequate compaction equipment approved by S.O. The finished level shall not vary more than ± 20 mm from the grade or level shown on the Drawings, or directed by the S.O. The material shall be spread and graded evenly over the width by motor grader or such other approved mechanical plant as directed by the S.O. When the pavement is spread adjacent to any structures, existing building or any physical features, extreme care shall be exercise as not to damage any existing physical feature and any damaged shall be made good or replaced at the Contractor ‘s own expenses. Compaction shall be completed as soon as possible by suitable compaction equipment and as directed by the S.O. Compaction and rolling operations shall begin along the edges and progress gradually towards the centre in a longitudinal direction. On super-elevated curves, the compaction and rolling shall begin at the low side and progress gradually towards the high side. Any rolling marks, ridges, cracks or irregularities which may developed during or after construction shall be corrected and the defective areas made good to the full thickness and recompacted.

10.40.4 Compaction

Compaction shall be a minimum soaked CBR of 20% when compacted to 95% of the maximum dry density determined in BS 1377 Compaction Test (4.5 kg rammer method) and soaked for 4 days under a surcharge of 4.5 kg.


136


Any reasonable compaction requirement or directed by the S.O. is deemed to be included in the Contract Rate.

10.40.5 Rectification of Surface

The surface of the prepared formation and the laterite pavement where it is not in compliance with the tolerance set out in Clause 10.40.3 unless the S.O. agrees, shall be rectified by the Contractor. All low spots shall be made up with approved fresh material as specified, laid and compacted to Specification. The defective area shall be scarified to a depth of 80 mm and corrected either by removal of material from high spots or by importation of further similar material to low spots. The area treated shall be not less than 15m long and 2 metre wide or such lengths to be determined by the S.O. necessary to obtain compliance with the Specification. The material removed from any high spot shall be run to waste and removed from the site at the Contractor’s own expense.


137

SECTION 11.0 – BRICKLAYER




138

All bricks used in the Works, unless otherwise shown in the Drawings, shall be hard, well burnt, machine made wire out clay bricks of R.I.B.A. standard size and from approved sources. They shall be regular in size and shape, with good faces and clean arises, undamaged, and free from all defects. Facing bricks shall be of the colour selected by the S.O. before any bricks are ordered samples shall be submitted to the S.O. for approval and all deliveries of bricks shall be up to the standard of the samples approved and kept on the site. All rejected bricks shall be removed from the site forthwith at the Contractor's own expenses.

The grading of the sand when determined as described in B.S. 812 shall be within the following limits :

% By Weight Passing B.S. Sieve

B.S. SIEVE 4.76 mm

2.40 µm

100

90-100

70-100

40-100

40-80

5-70

11.0 BRICKLAYER

11.1 Bricks

11.2 Cement

The cement, unless otherwise described, shall be ordinary Portland cement complying with B.S. 12.

11.3 Sand for Mortar

Sand for mortar shall be natural sand obtained from rivers or approved pits and shall be hard durable clean and free adherent coats such as clay and from clay pellets. It shall not contain harmful organic impurities or harmful materials such as iron pyrites salt coal mica shale laminated or flaky or elongated particles in such a form or in sufficient quantities to affect adversely the hardening strength or durability of the mortar or as might attack the reinforcement in reinforced brickwork. The S.O.'s decision as to the suitability of any sand shall be final.

mm

1.20 mm

600 µm

300

150 µm

Sands for general purpose mortar

Sands for reinforced brickwork mortar

100

90-100

70-100

5-40

0-15

0-10



139

Water shall be fresh, clean of potable quality, free of vegetation and other deleterious matters and shall comply with B.S. 3146.

11.5 Mortar Mortar for brickwork below D.P.C. level, piers and bearing wall shall consist of one part of cement to three parts of sand by volume and shall be made in as small quantities as is required and shall be used within half an hour of mixing.

11.6 Mixing Mortar

The ingredients for the mortars shall be measured in proper gauging boxes and a boarded platform shall be used for mixing. The mixture shall be thoroughly mixed dry after which only sufficient water shall be added with fine rose and the mass thoroughly mixed again to produce a uniform material of good consistency. No re-making up of partially set mortar shall be permitted.

Bricks shall be carefully handled from carts or lorries and stacked and all broken bricks shall be removed from the site without delay.

New brickwork shall be protected from the sun and kept moist for at least one day after it has been built. The tops of all walls where work has stopped shall be made thoroughly wet immediately before further work is commenced. All brickwork shall be constructed in English bond unless otherwise specified and shall be carried out perfectly true and plumb through successive courses so that no part of the work is more than 900mm above any adjacent brickwork. No overhang work will be permitted and scaffolding shall be carried up as the work proceeds.

11.4 Water

Mortar for brickwork above D.P.C. level shall be composed of one part of cement and six parts of sand with the addition of an approved mortar plasticiser used strictly in accordance with the manufacturer's instruction.

11.7 Brick Laying

All bricks shall be soaked in water for at least half an hour immediately before being laid and shall then be kept wet until they are set in the structure.

Bed and vertical joints of brickwork shall be filled solid with mortar and no vertical joint shall be allowed to be flushed up from the top each joint must be filled up as the bricks are laid. All work found out to comply strictly with this requirement shall be taken down and rebuilt at the Contractor's expense.


Joints shall not be more than 6mm in thickness and all joints shall be raked out to a depth of 12mm to form a key for plastering as the work proceeds. All wall angles piers, plasters and other brickwork shall be properly bonded together in the best approved manner. No broken bricks shall be used except when bricks cut to the correct size and shape are used to form the bond.

11.8 Half-Brick Walls Half-brick walls shall be built in stretcher bond and shall be reinforced at every fourth course with "Exmet" or other approved brick reinforcement, commencing two courses above floor level.

11.11 Lintels

Build in cramps, cramps for metal windows, doors, frames and precast units where shown and wherever required. Wrot-iron cramps shall be 38mm

All brickwork adjacent to reinforced concrete shall be bonded to the concrete structure with approved ties set at every fourth course. The ties shall be adequately secured to the main reinforcement in the concrete.

11.9 Facing Brickwork

All facing brickwork shall be executed in first quality approved racing bricks in Stretcher or Flemish bond as shown, properly bonded into any backing walls, piers, etc. Joints shall be raked out to a depth of 13mm and pointed up in coloured cement mortar to approved tints, finished with a neat struck weathered joint.

11.10 Damp Proof Course

Provide and lay where shown on drawings bituminuos sheet damp-proof course composed of "Plurex" or other approved hessian-based bituminous D.P.C. complying with B.S. 743 and weighing not less than 3.8 kilogram per square metre. It shall be lapped at least 75mm at angles and joints and shall be laid on 20mm thick bed of cement/sand (1:1) mortar coated with bitumen on the upper surface.

Unless otherwise shown all brickwork over openings shall be supported on precast concrete lintels in accordance with the dimension shown on the drawing or as directed by the S.O.

11.12 Building In

x 6mm x 225mm long for fixing wooden frames, etc. On end of the cramp shall be turned up and screwed to the frame and the other end shall be split and fish-tailed for building in. Cramps shall be embedded in concrete and built in as the brickwork proceeds.


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11.13 Scaffolding 11.13 Scaffolding

All scaffolding must be self supporting and independent of the building. No scaffolding bearers supported on the walls of the building under construction.

All scaffolding must be self supporting and independent of the building. No scaffolding bearers supported on the walls of the building under construction.

11.14 Valve Chambers and Manholes 11.14 Valve Chambers and Manholes a) Valve chambers and manholes where necessary shall be provided and

constructed. Chambers and manholes shall be of 225mm brickworks set in cement mortar.

a) Valve chambers and manholes where necessary shall be provided and constructed. Chambers and manholes shall be of 225mm brickworks set in cement mortar.

Unless approved by the S.O. the bottom of all manholes shall be benched up with Grade 20 concrete to an average thickness of 200mm and requisite half round channels shall be formed. The internal sides and the bottom of all manholes shall be rendered with 1:3 cement sand mortar 12mm thick.

Unless approved by the S.O. the bottom of all manholes shall be benched up with Grade 20 concrete to an average thickness of 200mm and requisite half round channels shall be formed. The internal sides and the bottom of all manholes shall be rendered with 1:3 cement sand mortar 12mm thick.

b) The pipes, specials and valves in the valve chambers shall be set in

Grade 20 concrete blocks to exact line and level prior to the construction of the chamber walls and all parts of the pipes and specials which are to be encased in concrete shall be brushed clean of their respective coatings.

b) The pipes, specials and valves in the valve chambers shall be set in Grade 20 concrete blocks to exact line and level prior to the construction of the chamber walls and all parts of the pipes and specials which are to be encased in concrete shall be brushed clean of their respective coatings.

11.15 Payment for Brickwork 11.15 Payment for Brickwork

Brickwork shall be measured in square metres for the net quantity erected, and no allowances shall be made for cutting and wastage. The Contract Rates shall include the cost of providing the bricks and mortar, all cutting and fitting to reinforced concrete, forming sill, reveals, notches and rebates and all openings, plumbing quoins and angles, raking out joints for keying and subsequent pointing up for flashings and damp proof course, for the supply and fixing of all galvanised steel expanded metal lath, and for all other specified work in connection with bricks and bricklaying for which no separate items are provided in the Bill of Quantities.

Brickwork shall be measured in square metres for the net quantity erected, and no allowances shall be made for cutting and wastage. The Contract Rates shall include the cost of providing the bricks and mortar, all cutting and fitting to reinforced concrete, forming sill, reveals, notches and rebates and all openings, plumbing quoins and angles, raking out joints for keying and subsequent pointing up for flashings and damp proof course, for the supply and fixing of all galvanised steel expanded metal lath, and for all other specified work in connection with bricks and bricklaying for which no separate items are provided in the Bill of Quantities. Where chases shall be cut, as instructed by the S.O. to accommodate cables and instrumentation, the Contract Rates for such work shall include cutting recesses for switches.

Where chases shall be cut, as instructed by the S.O. to accommodate cables and instrumentation, the Contract Rates for such work shall include cutting recesses for switches.



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SECTION 12.0 – STEEL AND METAL WORKS



Steelwork shall be thoroughly descaled to BS 4232 second quality and shall be painted with two coats of two pack epoxy based red lead primer before leaving the manufacturer's works. Any damage to this coating shall be repainted before erection.

Bolts, ragbolts, nuts and washers shall conform to BS 15 as regards material and BS 916 as regards dimensions. Each bolt shall be provided with two washers and bolts shall be long enough to show a full thread through the nut after fixing. All bolts, ragbolts, nuts and washers shall be hot-dip galvanised in accordance with BS 729.

The sizes of chequer plates shall be such that no discernible deflection occurs under the weights of a man standing upon it. Where it is not practicable to provide individual frames to each plate, the plates shall be stiffened by welding steel angles on their underside to eliminate discernible deflection. The plate panel sizes shall be such that they can be lifted by two men easily and each panel shall be provided with suitable sized lifting holes.

12.0 STEEL AND METAL WORKS 12.1 Structural Steel Work

Structural steel work shall conform to the requirements of BS 449; steel shall comply with BS 15, BS 548, BS 968 whichever is appropriate and steel tubes for structural purposes shall comply with BS 1775 and shall be obtained from a manufacturer to the prior approval of the S.O.

12.2 Bolts and Nuts

12.3 Steel Chequered Plate Chequer plating shall be mild steel and shall have a non-slip pattern on its upper face. Chequer plates shall be securely bolted with countersunk screw studs to frames set in the edges of and spanning the ducts or opening. Chequer plates for use in valve chambers or manholes shall be hinged to one side of the frames unless otherwise specified.

The edges of all chequer plates shall be finished straight or to the outline of obstructions and shall be free of burn marks or irregularities. Chequer plating which has been cut with a torch shall afterwards be ground to present a straight edge. Chequer plating shall be thoroughly wire brushed and painted with two coats of two pack epoxy based red lead primer before delivery. After installation on Site chequer plates sued in valve chambers shall be painted with a further two coats of two pack coal tar epoxy paint. Chequer plates used elsewhere shall be painted on the lower (hidden) upper (exposed) surfaces with one undercoat, two coats of semi-gloss high finishing paint of approved quality and colour.


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12.4 Handrailing Handrailing shall be made from hot-dip galvanised mild steel hollow sections and flats. After cleaning with lithoform, it shall be painted with two coats of two pack epoxy red lead primer, an undercoat and a further 2 coats of an approved gloss paint after installation. Expansion units shall be provided where the handrailings are more than 15 metre long. Where safety chains are required, they are to be galvanised mild steel 10mm nominal size, short links, smooth welded chains in accordance with BS 4942 Part 2. Each length of chain shall be fitted with a shackle at one end and a nap fastening at the other. The rates for handrailing shall include for painting and formation and subsequent grouting up of pockets in the concrete for stanchions.

12.5 Ladder Mild steel ladders shall be hot-dip galvanised in accordance with BS 729. After cleaning with lithoform it shall be painted with two coats of approved two pack coal tar epoxy paint which shall be obtained from an approved manufacturer. Unless detailed on the Drawings, the Contractor shall submit to the S.O. detailed drawings of the ladder for approval before placing any orders. Steel ladders shall be 450mm wide, of welded construction and shall not have an unsupported length of more than 2 metre. Intermediate support between the ends of the ladder shall be by means of stays securely fixed to the nearest part of the structure. The steel ladders shall be galvanised before leaving the manufacturers' works and the Contract Rates for supplying and fixing steel ladders shall include for painting as specified, and for all nuts, bolts, stays and other things necessary for fixing the ladders securely in place.

12.6 Step Irons Steel irons for use in chambers shall unless otherwise specified be bent from 25mm diameter mild steel bars to the shape and dimensions shown on the

Drawings and shall be hot-dip galvanised after bending. Step irons shall be measured by number and the Contract Rates for step irons shall include for the supply and all necessary fixing work galvanising and painting with 2 coats of approved two pack coal tar epoxy paint.

12.7 Fencing Fencing shall be as detailed on the Drawings. Chain link for fencing shall be PVC coated and consist of hot dipped galvanised 3.7mm wire of 50mm square mesh reinforced with 3 nos. 4.1 mm


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hot dipped galvanised line wires. Barbed wires shall be galvanised two ply 2.64 mm with 4 point barbs spaced at 75 mm interval.

Fence posts shall be of 64mm x 64mm x 9.4mm hot dipped galvanised mild steel angles spaced at 3.0 metre intervals with straining posts at all corners and at intervals of 15 metre. Stays for straining posts shall be 51mm x 51mm x 6.3mm hot dipped galvanised mild steel angles raked at 45o. All mild steel angles shall be galvanised and painted in accordance with BS 5493. All fence posts and struts shall be sunk into post holes 300mm x 300mm x 750mm deep, and filled in with Grade 20 concrete to be flushed with ground level. Suitable gate as shown in the drawings shall be provided to match the fencing. This gate shall be complete with lock gears and a 75mm lock of approved brand. Four (4) keys shall be provided for the locks. The Contract Rates for fencing and gate shall include for the supply of all materials, galvanising, excavation, erection of the fencing complete painting with 2 coats of approved paint, fence posts, stays corner posts, concrete support and dwarf walls. Payment will be made for the net length of fencing and number of gate erected.

12.8 Aluminium Structures and Sections

Aluminium structures shall be constructed in alloy NE8M to BS 1474. Cold working shall be avoided. All hollow boxed and pressed sections shall be extruded from fully heat treated aluminium alloy and etched and anodised in bronze colour to BS 1615. Recesses on internal faces of boxed sections shall be finished with a strip of 13mm x 6.5mm black vinyl glued on. Where aluminium members are in contact with other non-aluminium structures the contact faces shall be protected by insulating pads of neoprene bitumen alloy.

12.9 Galvanised Metals

All metals to be galvanised shall be of the full dimensions shown or specified and all punching, cutting, drilling, screw tapping, welding and the removal of burrs shall be completed before the galvanising process commences. All galvanising shall be done by the hot-dip process with spilter, not less than 98% of which shall be pure zinc. Bolts, nuts and washers shall be completely galvanised including the threads but galvanising removed in the course of nut fixing may be replaced with an approved zinc rich paint.

The galvanising shall be uniform, clean, smooth and as free from spangle as possible. It shall weigh not less than 6.00 grams per square metre of area covered and be not less than 0.1mm thick.


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All galvanised metal parts shall be protected from damage due to electrolytic action, white rust and abrasion during delivery, storage and erection. Minor damage shall be touched up with an approved zinc chromate or other approved metallic compound but if, in the opinion of the S.O. the damage to the galvanising is too severe or extensive the part shall be removed and be re-galvanised.



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The Contractor shall not use fixtures and fittings for metalwork including pipework in which dissimilar metals likely to lead to galvanic action are placed in permanent contact with each other.

Rain water pipes shall be measured as the net length erected in place and shall include for all works in forming bends where required, cutting, jointing and building into concrete, providing and erecting support brackets for holding the pipe in position.

12.10 Dissimilar Metals

12.11 Rain Water Pipes uPVC rain water down pipes and fittings shall be obtained from an approved manufacturer. They shall be formed into required lengths where necessary by an approved method recommended by the suppliers. Steel rain water pipes and fittings shall be of hot dipped galvanised no. 16 SWG pressed steel sheets and rectangular in cross-section. They shall be formed into required lengths by an approved method of soldering and properly secured with 50mm x 0.8mm galvanised sheet iron straps spaced at approximately 1800mm centre. After erection all exposed surfaces shall be cleaned down with lithoform and painted with one flat undercoat and two high gloss finishing coats of paint of approved quality.

12.12 Open Mesh Flooring Open mesh flooring shall be fabricated from mild steel load bearing bars of flat section bared with round, square, or twisted square bars perpendicular to and welded to each load bearing bar. Panels shall be trimmed across the ends of load bearing bars by flats of the same cross-section welded to each load bearing bar. Cut-outs for plant items shall be trimmed with curved or straight edge trimmings as appropriate. Panels shall be fixed to angle kerbing or supporting steelwork with adequate clips so that movement is prevented.

12.13 Manhole Covers, Surface Boxes, etc.

Ductile iron manhole and access covers, surface boxes, gulley grating and frames shall be obtained from an approved manufacturer and shall comply generally with BS 497. Items not covered by this standard shall be of a quality equal to the first grade available in the country. Access covers and surface boxes exposed to the weather shall incorporate a waterproof seal. Frames shall be firmly bedded in 1:3 cement/sand mortar and the tops of all covers and gratings shall be flush with the finished surface of the surrounding floor, ground for pavement. Four sets of each type of lifting key shall be supplied by the Contractor.

saj_specs

Documents

expansion joints pipes

sheathing of ms pipes

polyethylene pe pipes

di pipes protection

handling records of

mild steel pipes

ductile iron pipes

pipes of different type