concrete

Concrete

ES-14-202-10

Version No. 7.0 Page 1 of 24

Document last modified: 07 January 2013. Date printed: 17 January 2013.

This is a Controlled Document that complies with Wesfarmers Chemicals, Energy & Fertilisers formatting and Quality Control standards.

Please check that this is the latest available version before use.

Title: CONCRETE

Number: ES-14-202-10

Version Number: 7.0

Date Revised: 07 January 2013

Owner: Harish Chopra

Authoriser: Manoj Thakur

Reasons for Creating or Amending Document

Full Review of Document and Profile - No Change

Actual Change Details: Full review of document and profile carried out - No Changes Required

TABLE OF CONTENTS

1. SCOPE ........................................................................................................................................... 3

2. DEFINITION OF TERMS .......................................................................................................... 3

3. STANDARDS ................................................................................................................................ 4

4. CONCRETE MATERIALS ........................................................................................................ 5

4.1 CEMENT ................................................................................................................................ 5 4.2 AGGREGATES ..................................................................................................................... 5 4.3 WATER .................................................................................................................................. 5 4.4 ADMIXTURES ...................................................................................................................... 5 4.5 CONCRETE STRENGTH ..................................................................................................... 6

5. STEEL REINFORCEMENT ...................................................................................................... 7

5.1 STEEL FOR REINFORCEMENT ......................................................................................... 7 5.2 TEST CERTIFICATES .......................................................................................................... 7 5.3 REINFORCEMENT SCHEDULES ....................................................................................... 7 5.4 ON-SITE IDENTIFICATION ................................................................................................ 8 5.5 STEEL TO BE KEPT CLEAN............................................................................................... 8

6. ACCESSORY ITEMS .................................................................................................................. 8

6.1 HOLDING DOWN BOLTS ................................................................................................... 8 6.2 STRUCTURAL STEEL INSERTS AND SLEEVES ............................................................ 8 6.3 WATER STOPS ..................................................................................................................... 8

Concrete

ES-14-202-10



6.4 EXPANSION JOINT FILLER ............................................................................................... 8 6.5 JOINT SEALING COMPOUND ........................................................................................... 9 6.6 VAPOUR BARRIER ............................................................................................................. 9 6.7 CURING COMPOUND ......................................................................................................... 9

7. CSBP SUPPLIED CONCRETE .................................................................................................. 9

8. EARTHWORKS ........................................................................................................................ 10

8.1 TERMITE TREATMENT .................................................................................................... 10 8.2 VAPOUR BARRIER ........................................................................................................... 10

9. FORMWORK ............................................................................................................................. 10

9.1 FORMWORK – FIXING ..................................................................................................... 10 9.2 OPENINGS IN FORMWORK ............................................................................................. 11 9.3 HOLDING DOWN BOLTS ................................................................................................. 11 9.4 EMBEDDED ITEMS ........................................................................................................... 12 9.5 REMOVAL OF FORMWORK ............................................................................................ 12 9.6 USE OF PERMANENT FORMWORK ............................................................................... 13

10. REINFORCING STEEL ........................................................................................................ 13

10.1 STEEL FOR REINFORCEMENT ....................................................................................... 13 10.2 BENDING ............................................................................................................................ 13 10.3 FIXING ................................................................................................................................ 13 10.4 WELDING OF REINFORCEMENT ................................................................................... 14 10.5 COVER ................................................................................................................................ 14

11. PRE-CONCRETE POUR INSPECTION ............................................................................. 14

12. CONCRETE WORK .............................................................................................................. 15

12.1 PLACEMENT AND COMPACTION OF CONCRETE ..................................................... 15 12.2 JOINTS IN SLABS AND PAVEMENTS ............................................................................ 16 12.3 TOLERANCES .................................................................................................................... 17 12.4 FINISH REQUIREMENTS ................................................................................................. 19 12.5 CURING ............................................................................................................................... 20 12.6 HOT WEATHER REQUIREMENTS .................................................................................. 21 12.7 BLINDING CONCRETE ..................................................................................................... 22 12.8 PUMPED CONCRETE ........................................................................................................ 22 12.9 DEFECTS IN FORMED SURFACES ................................................................................. 23 12.10 HOLES TO BE FILLED ..................................................................................................... 23

13. TESTING ................................................................................................................................. 24

13.1 GENERAL ........................................................................................................................... 24 13.2 PROJECT CONTROL TESTING ........................................................................................ 24

TABLES

Table 1 Concrete Application Grades .............................................................................................. 6

Table 2 Recommended Slump ......................................................................................................... 7

Table 3 Tolerances in Concrete Work ........................................................................................... 18

Concrete

ES-14-202-10



1. SCOPE

This Standard establishes the minimum technical requirements for materials, workmanship and inspection to be used for concrete work.

2. DEFINITION OF TERMS

Supplier

The Company, that supplies concrete, steel reinforcing and accessory items.

Contractor

The Company, that installs concrete, steel reinforcing and accessory items.

Sub-Contractor

A third party to be employed by the Contractor who has been approved by the Superintendent.

Superintendent

CSBP Limited, or authorised representative.

CSBP

CSBP Limited.

Works

The Scope of Work that a Contractor is or may be required to execute under an agreement including variations and remedial work.

Actions

• Shall, Will or Must - indicates mandatory action.

• Should - indicates preferred/recommended action.

• May or Can - indicates possible or optional action.

Concrete

ES-14-202-10



3. STANDARDS

The Contractor shall perform the Works in accordance with this Standard, the latest issue of referenced Standards and Contractor regulations for on-site work. Should there be conflict between the Works, Drawings and the Standards, the Contractor shall notify the Superintendent in writing for resolution. In general, the most stringent requirement will prevail.

CSBP Engineering Standards

ES-14-202-01 Earthworks & Site Preparation

ES-14-202-11 Protective Coatings for Concrete

ES-14-202-12 Concrete Repairs

ES-14-202-14 Grouting

CSBP Guide Manuals

GM-10-020-04 Contractors’ Site Instructions

GM-11-031-51 Work Permit System

GM-11-035-02 Basic Safety Rules

CSBP Standard Forms

SF1905 Concrete Approval Checklist

Standards Association Of Australia

Concrete

AS1012 Methods of Testing Concrete Part 1 - Sampling of Fresh Concrete Part 8 - Concrete Test Specimens Part 12 - Density of Hardened Concrete Part 14 - Test Samples from Hardened Concrete AS1289 Methods of Testing Soils for Engineering Purposes AS1379 Specification and Supply of Concrete AS1478 Chemical Admixtures for Concrete AS2349 Method of Sampling Portland and Blended Cements AS2350 Methods of Testing Portland and Blended Cements AS2758 Aggregates and Rock for Engineering Purposes Part 1 - Concrete Aggregates AS3582 Supplementary Cementitious Materials for use with Portland and Blended Cement AS3583 Methods of Test for Supplementary Cementitious Materials for use with Portland

and Blended Cement AS3600 Concrete Structures AS3610 Formwork for Concrete AS3972 Portland and Blended Cements

Concrete

ES-14-202-10



Reinforcing Steel

AS1302 Steel Reinforcing Bars for Concrete

AS1303 Steel Reinforcing Wire for Concrete

AS1304 Welded Wire Reinforcing Fabric for Concrete

AS1554 Structural Steel Welding

Steel Items

AS1214 Hot-Dip Galvanised Coatings on Threaded Fasteners

AS3678 Structural Steel Hot-Rolled Plates, Floor Plates and Slabs

AS3679 Structural Steel

Part 1 – Hot Rolled Bars & Sections

Part 2 – Welded I Sections

AS4100 Steel Structures

AS4680 Hot-Dip Galvanised (Zinc) Coatings on Fabricated Ferrous Articles

4. CONCRETE MATERIALS

4.1 CEMENT

Ready-mixed concrete shall conform to AS3600 and AS1379 using Portland Type GP, in accordance with AS3972, unless specified otherwise.

4.2 AGGREGATES

For normal concrete grades N20-N50, grading sizes shall comply with the requirements of AS3600.

Course aggregate shall consist of crushed stone conforming to the requirements of AS2758.1.

Fine aggregate shall consist of clean, crisp, sharp pit sand from an approved source complying with AS2758.1.

4.3 WATER

Water shall be clean, fresh and free from oil, acid, alkali, organic matter and other deleterious substances.

The maximum combined total soluble chloride content of the water and aggregate shall not exceed 0.5kg/m3.

4.4 ADMIXTURES

Admixtures may be added to improve the workability of concrete with the approval of the Superintendent.

Admixtures shall comply with the requirements of AS1478 and the Contractor shall supply evidence to the Superintendent to demonstrate compliance with these requirements.

Concrete

ES-14-202-10



4.5 CONCRETE STRENGTH

4.5.1 Concrete Grades

Table 1 shows grades of concrete, the characteristic compressive strengths at twenty-eight (28) days and the main applications for the various grades of concrete. Concrete characteristic compressive strengths shall conform to these grades unless otherwise noted in the Works or on the Drawings.

GRADE CHARACTERISTIC

STRENGTH (MPa @ 28 DAYS)

APPLICATION

S15 15 Blinding concrete

N20 20 Plain concrete, backfill for block work walls

N25 25 Floor slabs - totally enclosed buildings

N32 32 Footings, ground slabs, general areas exposed concrete

S32 32 Low Heat Mix - large pours

N40 40 Suspended slabs

S45 45 Process area slabs exposed to caustic/acid solutions

N50 50 Special applications

Table 1- Concrete Application Grades

Note: Seven day strengths may not be sufficient for structures requiring early load carrying capacity (long span members must not be loaded early regardless of concrete strength). Refer to AS1379 Table 2 for mean 7-day strengths of ‘normal’ class concrete.

4.5.2 Minimum Cement Content

Cement content of all concrete of strength F’c = 25 MPa and higher shall be 300 kg/m3 minimum.

4.5.3 Maximum Water/Cement Ratio

The water/cement ratio for all concrete strengths of 25MPa and higher shall not exceed 0.5.

Note: Minimum cement contents and water/cement ratios shall be shown on drawings and in specifications if the ratios in this Standard are not desirable for certain applications, eg. water retaining structures, marine environments, etc.

4.5.4 Slumps

The concrete shall have a slump similar to the recommended slump, which will be used for the various types of construction as shown in Table 2.

On no account shall water or any other admixtures be added to the concrete supplied to site to adjust the slump or vary the texture, without the approval of the Superintendent.

Concrete

ES-14-202-10



TYPE OF CONSTRUCTION DESIGN SLUMP TARGET TOLERANCE

Reinforced foundation walls and footings 80 mm ± 15 mm

Plain footings, caissons and substructure walls 60 mm + 15 mm / - 0 mm

Slabs, beams and reinforced walls 80 mm + 15 mm / - 0 mm

Building columns 80 mm + 0 mm / - 15mm

Pavements 60 mm + 15 mm / - 0mm

Table 2 - Recommended Slump

4.5.5 Workability

The concrete shall be cohesive and of such consistency that it can readily be worked into the corners and angles of formwork and around steel reinforcement without permitting the concrete to segregate, or free water to collect at the surface. On striking the forms, the concrete shall present a fair face, free from honeycombing, surface crazing or excessive dusting.

Workability and slump shall be measured in accordance with AS1012.

Note: Any restrictions on the method of placing which may require the Contractor to use pumped concrete only should be elaborated in the Works.

5. STEEL REINFORCEMENT

5.1 STEEL FOR REINFORCEMENT

Unless specified otherwise on the Drawings or in the Works, material shall be in accordance with:

a. AS1302 – Grade 250R for plain bars.

b. AS1302 – Grade 400Y for deformed bars.

c. AS1303 for hard drawn steel wire reinforcement.

d. AS1304 for steel wire reinforcing fabric.

5.2 TEST CERTIFICATES

The Contractor shall, where requested to do so, supply to the Superintendent copies of test certificates confirming that all steel complies with the Standard.

5.3 REINFORCEMENT SCHEDULES

The Contractor shall submit one copy of the steel reinforcement schedules including a marking plan if applicable to the Superintendent. The responsibility for ensuring that the reinforcing is bent, supplied and placed according to the Drawings rests entirely with the Contractor.

Concrete

ES-14-202-10



5.4 ON-SITE IDENTIFICATION

The Contractor shall separately stack the different types of reinforcement clear of ground and label for positive identification.

5.5 STEEL TO BE KEPT CLEAN

All reinforcing steel bars shall be free from loose rust, mill scale, oil or other coating which is liable to weaken the bond between concrete and steel. Any bars so affected shall be cleaned to the satisfaction of the Superintendent or replaced.

6. ACCESSORY ITEMS

6.1 HOLDING DOWN BOLTS

Cast in holding down bolts shall be fabricated as shown on the Drawings and supplied complete with one nut and washer. Material shall be of galvanised Grade 250 steel conforming to AS3679 and AS1214 unless otherwise specified.

Higher-grade steel such as Grade 410 shall only be used when specified in writing by the Superintendent.

Note: Location of any holding down bolts to be supplied ‘By Others’ or where non-standard washers are to be used (e.g. oversize holes in base plates) shall be specified in the Drawings or Works.

6.2 STRUCTURAL STEEL INSERTS AND SLEEVES

Structural steel inserts shall conform to AS3678 and AS3679. Welding of fabricated inserts shall comply with AS1554. Pipe sleeves shall be Schedule 40 black steel unless otherwise specified on the drawings. The surfaces of items to be embedded in concrete shall be cleaned but left unpainted.

Note: Location of any inserts or sleeves to be supplied ‘By Others’ or surfaces to be treated shall be specified in the Drawings or Works.

6.3 WATER STOPS

Cast-in-place plastic stops shall be of the backstop type approved by the Superintendent. Details shall be as indicated on standard drawings.

Splicing of water stops shall be in accordance with the manufacturer’s recommendations.

Steel water stops shall be mild steel with joints and thicknesses as shown on the Drawings.

6.4 EXPANSION JOINT FILLER

Expansion joint filler board material shall be a Superintendent approved closed cell polyester foam type, such as Nitoseal Cellox or approved equivalent.

Concrete

ES-14-202-10



6.5 JOINT SEALING COMPOUND

Joint sealing compound shall be a Superintendent approved two-part polyurethane flexible setting mastic such as Secoseal 200 or approved equivalent, unless otherwise specified on the Drawings.

6.6 VAPOUR BARRIER

Vapour barrier where required by the Superintendent shall be 0.2mm thick polyethylene sheeting.

6.7 CURING COMPOUND

Membrane curing compound shall be either:

a. Fosroc Concure WB30 (Parbury Technologies),

b. Maxcure WB (Epirez),

c. Sikagard – 680S (Sika Aust Pty Ltd),

d. An approved equivalent.

7. CSBP SUPPLIED CONCRETE

When concrete is nominated in the Works as being CSBP supplied, then the following shall apply:

a. CSBP will pay for the supply of the concrete and all testing.

b. The Contractor shall pay for any concrete used which exceeds 5% of the calculated volume of each pour.

c. The Contractor shall pay for all wasted concrete if, due to over ordering, more than 0.5 cubic metres must be wasted.

d. CSBP supplied concrete shall conform to this Standard. Any variations to the concrete supplied as required by the Contractor are subject to the approval of the Superintendent.

e. The Contractor will not be required to assume the responsibility for the quality of the concrete supplied. However, the Contractor must inform the Superintendent immediately if in the opinion of the Contractor, any concrete delivered to the site does not comply with this Standard.

f. The Contractor is responsible for:

1. Accurate estimating and ordering of concrete.

2. Ordering the correct class of concrete.

3. Providing suitable access for trucks.

4. Any expenses incurred due to unreasonable delays caused by the Contractor.

g. All operations following discharge of the concrete from the truck (excluding project control testing).

Concrete

ES-14-202-10



8. EARTHWORKS

For site clearing, excavation, filling, compaction, inspection, testing and finishing of earthworks, refer to CSBP Engineering Standard Earthworks & Site Preparation (ES-14-202-01).

8.1 TERMITE TREATMENT

Subgrade slabs for architectural buildings shall have a Superintendent approved termite treatment applied prior to placement of a vapour barrier.

8.2 VAPOUR BARRIER

Following final grading, an approved vapour barrier (refer Section 6.6) shall be installed over the subgrade. Care shall be taken to ensure continuity of the vapour barrier over the entire area to be covered. All splices shall be lapped as recommended by the manufacturer. Laps, punctures and tears shall be sealed with vapour barrier tape.

9. FORMWORK

9.1 FORMWORK – FIXING

All formwork shall be constructed of timber, sheet metal or other approved material applicable to the class of finish required. The formwork shall be firmly supported, adequately strutted, braced and tied to withstand the placing and vibration of concrete and the effects of weather.

The formwork shall comply with AS3610. The Contractor shall be responsible for the calculations and design for the structural adequacy of the formwork and if required, shall submit these to the Superintendent for approval before construction.

On formwork to external concrete which will be permanently exposed, all horizontal and vertical joints and formwork ties shall be so arranged that joint lines and formwork tie lines will form a uniform pattern on the face of the concrete.

Faces of formwork that will be in contact with concrete shall be free from adhering foreign matters, projecting rails, splits and other defects. All formwork shall be clean and free from standing water, dirt, shavings and other foreign matter.

Formwork shall be provided for the top surfaces of sloping work where the slope exceeds fifteen degrees from the horizontal and shall be anchored to enable the concrete to be properly compacted and to prevent flotation, care being taken to prevent air being trapped.

Opening for inspection of the inside of the formwork and for the removal of water used for washing down, shall be provided and so formed as to be easily closed before placing concrete. Before placing concrete all bolts, pipes or conduits or any other fixtures which are to be built in shall be fixed in their correct positions, and cores and other devices for forming holes shall be held fast by fixing to the formwork or otherwise. Holes shall not be cut in any concrete without the approval of the Superintendent.

All exterior angles on the finished concrete of 90° shall be given 20mm x 20mm chamfers unless otherwise required by the Superintendent.

Concrete

ES-14-202-10



No ties or bolts or other devices shall be built into the concrete for the purpose of supporting formwork without the prior approval of the Superintendent. The whole or part of any such support shall be capable of being removed so that no part remaining embedded in the concrete shall be nearer than 60mm from the surface in the case of reinforced concrete and 150mm in the case of unreinforced concrete. Holes left after removal of such supports shall be neatly filled.

Formwork in contact with the concrete shall be treated with suitable non-staining mould oil to prevent adherence of the concrete except where the surface is subsequently to be rendered. Care shall be taken to prevent the oil from coming into contact with reinforcement or with concrete at construction joints.

Surface retarding agents shall be used only where approved by the Superintendent.

9.2 OPENINGS IN FORMWORK

The Contractor shall provide openings, pockets, and chases required in concrete piers, walls and floors, as detailed on the drawings. The Contractor shall confirm the location of any cast in items (such as electrical conduits) prior to placement of concrete.

Note: Electrical layout drawings shall be checked for openings required for cable ladders and embedded conduit that may not be shown on concrete drawings. The Contractor is to supply and install cast in conduit, where required, prior to pouring.

9.3 HOLDING DOWN BOLTS

Refer to 6.1 for holding down bolt materials.

The Contractor shall accurately set out centre lines, orientation and levels to ensure the maximum accuracy of placement of the holding down bolts.

Where practicable, the Contractor should fabricate a group of holding down bolts into a cage to simplify the positioning of the bolts.

Placement of holding down bolts shall be in accordance with AS4100 Section 15.3.1 tolerances as follows:

± 3mm centre to centre of bolts in a group

± 6mm centre to centre of adjacent groups

All new works shall use cast in holding down bolts.

Chemical or expanding wedge anchors shall only be used on major structural or mechanical items when making additions or changes to existing work except where specified by the Superintendent. Minimum edge distances and spacings set by the anchor manufacturer shall be maintained at all times when expanding wedge anchors are used.

The Contractor shall place holding down bolts accurately in position and to the correct level. The bolts shall be held securely against movement and the bolt threads shall be greased before the placement of concrete.

Concrete

ES-14-202-10



Immediately after the completion of concreting operations, the bolt threads shall be cleaned and regreased. Under no circumstances, shall any galvanised or other protective coating on the bolts be damaged.

After the concrete has hardened sufficiently, exposed portions of anchor bolts shall be cleaned of all concrete and the threads chased. Threads shall then be coated with grease, washers, and nuts installed and suitably wrapped.

9.4 EMBEDDED ITEMS

The Contractor shall locate the built-in steelwork items accurately in position and to the correct level, and shall ensure that they are securely held against movement throughout the concreting operations. The surface of the steelwork shall be cleaned down immediately after the completion of placement of the concrete.

Embedded items, including miscellaneous structural metal, kerb angles, pipe or sheet metal sleeves, water stops, wood nailers, joint formers, expansion joint material and other miscellaneous inserts are to be embedded in the concrete by the Contractor as specified or as shown on the drawings. At the time they are to be embedded they shall be unpainted, unless noted otherwise, and free from heavy rust scale, grease, oil or other surface coatings, which will reduce their bond to the concrete. The Contractor shall liaise with other trades on the site where inserts ‘Set by Others’ are required to ensure all such inserts are installed prior to pouring concrete.

All inserts shall be securely held in position and shall be rechecked by the Contractor immediately after the concrete is placed. Any change in position caused by the concrete placing operations shall be corrected immediately by the Contractor.

Inserts, except for approved plastic conduit, shall not be fastened or connected in any manner to either building column anchor bolts or to the building structural steel, nor shall they be welded to reinforcing steel, without prior approval of the Superintendent.

9.5 REMOVAL OF FORMWORK

Formwork shall be designed so as to permit easy removal without resorting to hammering or levering against the surface of the concrete.

Formwork stripping schedules shall be prepared by the Contractor and approved by the Superintendent. Schedules shall be developed based on imposed loads on the concrete and AS3600 requirements.

Formwork shall be removed in such a manner as not to endanger the safety of the structure. Where the structure as a whole is supported on shores, the removable floor forms, beams, columns and similar vertical forms may be removed no less than twenty-four hours after completion of concrete placement provided the concrete is sufficiently hard not to be damaged.

The supporting forms or shoring shall not be removed until the concrete members have acquired sufficient strength to support their weight and any incidental loading.

Other formwork shall not be removed until the concrete has obtained the minimum strength required by the specification.

Concrete

ES-14-202-10



All proposals for early stripping of forms must be referred to the Superintendent.

The Superintendent will indicate in the Works if high early concrete strength is required.

Note: Any structure that will require early strength to allow earlier usage or stripping time shall be specified in the Works or the Drawings.

9.6 USE OF PERMANENT FORMWORK

The approval of the Superintendent shall be obtained prior to the use of permanent formwork, such as Bondek. Slab thicknesses shall be adjusted, so that design cover to bottom reinforcement is maintained, regardless of any stiffening effects provided by the permanent formwork. Cover shall be measured to the top of the formwork rib. The Contractor shall install propping in accordance with the Manufacturers recommendations.

10. REINFORCING STEEL

10.1 STEEL FOR REINFORCEMENT

Material shall be in accordance with Section 5.1 unless otherwise specified on the Drawings or in the Works.

All bars shall be free from loose rust, mill scale, oil or other coating which is liable to weaken the bond between the concrete and steel. Any bars so affected shall be cleaned to the satisfaction of the Superintendent. Any bars that are pitted with rust will be rejected. Rust adhering to reinforcements after handling and placement will not require removal unless directed by the Superintendent.

10.2 BENDING

Bars shall be bent in accordance with the provisions of AS3600. All bending shall be carried out cold with the use of an approved bending machine. Re-bending of bent bars shall not be permitted unless approved by the Superintendent. Where such approval is given, the reinforcement shall be bent hot, at cherry-red heat (not exceeding 815°C) but shall not be cooled by quenching. Bars that depend on cold working for their strength shall not be subjected to heating either for the purpose of bending or cutting to length. Bent bars shall be adequately labelled and stacked so as to give ready identification.

The Contractor shall prepare and submit all bar bending schedules to the Superintendent for approval.

10.3 FIXING

The bars shall be firmly bound together at intersections with 1.6mm diameter soft annealed wire, to ensure that the framework of bars will retain its design form. The framework shall be temporarily supported as to retain its correct position in the formwork during the pouring and vibrating process.

Welded mesh reinforcement shall be laid in full sheets where possible.

Concrete

ES-14-202-10



During concreting, a competent steel fixer shall be in attendance on the work to adjust and correct the position of the reinforcement immediately prior to the placing of the concrete. In general, no temporary supports to the reinforcement will be allowed to be incorporated in the finished concrete, but in cases where it is essential for any temporary supports to be left in the concrete, such supports shall be of a size and type approved by the Superintendent.

If, in the opinion of the Superintendent, additional permanent supports are considered necessary for the satisfactory positioning of reinforcement, these and all stools between layers are to be provided by the Contractor at no additional cost.

10.4 WELDING OF REINFORCEMENT

Tack welding of anchor bolts, anchor ties or inserts to the steel reinforcement for positioning or anchorage shall not be permitted without prior approval of the Superintendent. Electrical conduits may be attached for support to reinforcing steel running transverse to the conduit.

10.5 COVER

All concrete shall be designed with the minimum concrete cover to the reinforcement being in accordance with Section 4 of AS3600 and installed as shown on the Drawings.

11. PRE-CONCRETE POUR INSPECTION

All concrete placements shall be controlled by the use of a CSBP Standard Form Concrete Approval Checklist (SF1905).

Prior to placing of concrete, the Superintendent will inspect all cast-in-concrete items and will sign the Checklist, thereby releasing concrete placement. The release of concrete placement by the Superintendent shall be interpreted solely as an acknowledgement that the Contractor has complied with established control procedures.

Concrete

ES-14-202-10



12. CONCRETE WORK

12.1 PLACEMENT AND COMPACTION OF CONCRETE

Before any concreting operation is commenced, the limits of each placement shall be determined by the Contractor and approved by the Superintendent. The limits of each placement shall take into account the possibility of inclement weather.

The Contractor shall make every effort to avoid placing concrete during wet weather and shall be responsible for the repair of all slabs affected by wet weather.

Before placing any concrete, all preliminary work such as cleaning the equipment for mixing and transporting the concrete, forms, reinforcing steel, and bearing strata shall be carefully checked and all debris and water removed. No concrete shall be poured until the CSBP Standard Form Concrete Approval Checklist (SF1905) has been signed off.

Concrete shall be conveyed from the concrete mixer to its final position without delay. Concrete shall be discharged at the site of the works from the delivery truck or agitator within one (1) hour of adding water to the mix.

The Contractor shall provide with each truck delivery of concrete, a docket showing the following information:

a. Quality of concrete. b. Concrete strength. c. Batching time. d. Nominal maximum aggregate size. e. Design slump.

If in the opinion of the Superintendent, the concrete in a load has not been adequately mixed or has segregated, it shall be further mixed to an approved consistency before any more concrete is discharged. No water shall be added to the mix on Site. Concrete that cannot be adequately mixed to the satisfaction of the Superintendent shall be removed from the Site.

Fresh concrete surfaces shall be protected from rain, hail, etc, with plastic sheeting, tarpaulins or other acceptable materials until the concrete has acquired final set.

Equipment for chuting, pumping and pneumatically conveying concrete shall be of such size and shape as to ensure a continuous flow of concrete at the delivery end without separation of materials.

The washing-out of concrete trucks and/or the depositing of surplus concrete shall be performed only in the areas designated by the Superintendent.

When the placement of concrete has commenced, it shall be carried on as a continuous operation until the pouring of the panel or element is completed.

Concrete shall be deposited as near as practicable to its final position to avoid segregation due to rehandling or movement. The rate of concreting shall be carried out such that the concrete is at all times plastic and flows readily into the spaces between steel reinforcement bars. No concrete that

Concrete

ES-14-202-10



has partially hardened or has been contaminated by foreign materials shall be deposited on the work, nor shall retempered concrete be used.

Concrete shall be thoroughly compacted by approved mechanical vibration during the operation of placing and shall be thoroughly worked around the reinforcement and embedded fixtures and into the corners of the forms. Vibration shall continue until air bubbles cease to rise to the surface to the approval of the Superintendent.

Where conditions make compacting difficult, or where the reinforcement is congested, batches of the same mortar as in the concrete, with the coarse aggregate omitted and having the same water/cement ratio, shall be first deposited in the forms to a depth not exceeding 25mm.

Each layer of concrete shall be soft when new horizontal layers are placed upon it. These layers shall not be deeper than 450mm. Care shall be taken to avoid vertical joins or inclined planes.

The Contractor shall prevent accumulation of hardened mortar on formwork or reinforcing steel when placing concrete, especially in thin sections or walls of considerable height.

Dropping of concrete in excess of two (2) metres shall not be permitted without permission from the Superintendent.

All concrete in paving, or in mass concrete of 300mm or more in depth, shall be worked into place by means of adequately sized mechanical vibrators. The entire depth of a new layer of concrete shall be vibrated and the vibrator shall penetrate at least 100mm into the layer below. Spading and rodding to ensure the proper placement of concrete and to avoid surface honeycombing shall supplement vibrators. At least one standby vibrator shall be provided in case of breakdown during the pour. Vibration shall continue until air bubbles cease to rise to the surface.

Unless authorised in writing by the Superintendent, concrete shall not be placed in water, nor shall water be allowed to rise over, drop onto, or flow through freshly placed concrete before it has acquired final set. In an emergency, or where conditions require the depositing of concrete in or through water, the concrete shall be placed through tremmies in an approved manner. Water vent pipes and drains shall be filled by grouting under pressure or as otherwise approved by the Superintendent after the concrete has thoroughly hardened.

12.2 JOINTS IN SLABS AND PAVEMENTS

12.2.1 Requirements

Joints shall be installed in slabs only at the specific request of the Superintendent. Such joints shall be fully detailed on the Drawings and Works.

12.2.2 Construction Joints

If the Contractor’s proposed method of construction requires the use of joints not specified by the Superintendent, the Contractor shall submit full details of such joints to and obtain written approval from the Superintendent before proceeding.

Concrete

ES-14-202-10



12.2.3 Waterbars

Care shall be taken, particularly when using ‘backstop’ waterbars to ensure the open ends of the waterbar are returned upwards and cast into the concrete, to prevent leakage of liquid into the subgrade from this drainage path.

12.2.4 Dowel Bars

The Superintendent, before and after pouring concrete shall approve alignment and orientation of dowel bars.

12.3 TOLERANCES

Deviation from established lines, grades and dimensions shall comply with Table 3 unless noted otherwise on the Drawings.

Concrete work that exceeds the tolerance limits shall be remedied or removed and replaced by the Contractor at the Contractor’s expense.

Permissible surface defects and depressions for exposed concrete surfaces specified in Section 12.4 of this Standard are to be distinguished from the dimensional tolerances specified in Table 3.

Concrete

ES-14-202-10



VARIATION DESCRIPTION TOLERANCE

Variation from plumb:

a. In the lines and surfaces of columns, piers, walls and in equipment foundations.

In 3.0m

In any storey or 6.0m

In buried construction twice the above amounts.

± 6mm

± 10mm

b. For exposed corner columns, control joint grooves and other conspicuous lines

In any bay or 6.0m

In 12.0m or more

± 6mm

± 12mm

Variation from the level or from grades shown on the drawings, except for grout caps.

In 3.0m

In any bay or 6.0m maximum

In 12.0m or more

± 6mm

± 10mm

± 20mm


Top of Pedestals or Plinths to receive shimmed or grouted steelwork

± 6mm

Top of Ring Beam for Steel Tanks:

a. Variation on Design Level ± 6mm

b. Rate of change in level in 9.00m ± 3mm

Variation from the level or from grades shown on the drawings for grout caps.

± 2mm

Variation of the linear building lines, or equipment foundations from established position in plan related position of column, walls or partitions.

In any bay or 6.00m maximum

In 12.00m or more


± 12mm

± 25mm

Table 3 - Tolerances in Concrete Work

Concrete

ES-14-202-10



12.4 FINISH REQUIREMENTS

12.4.1 General

The finish for all exposed concrete surfaces shall be off-form Class 3 to AS3610 unless noted otherwise on the Drawings. Repairing of surface defects and hand trimming will be required on exposed surfaces only where patching of honeycombing is necessary or where form design or construction or general workmanship produce gradual surface defects exceeding 6mm in a 3.0m straight edge or abrupt defects exceeding 1.5mm. Offsets caused by displaced or misplaced formwork sheeting or form sections, by loose knots in forms, or by otherwise defective form timbers will be considered as abrupt surface defects.

All concrete surfaces, both above and below the backfill levels shall have all metal form ties removed not less than 20mm back from the faces of the concrete. The holes shall be cleaned and wire brushed to remove all laitance, form oil, curing compound and other foreign material and filled with mortar. Refer to Section 12.10 for further details.

The surface of all substation and architectural building floors shall be finished to the elevations shown on the drawings, and shall show no depression more than 6mm under a 3.0m straight edge placed at 1.5m intervals and overlapping 1.5m on each check.

Concrete slabs that have a nominated grade for drainage shall not have local depressions that are capable of holding water.

Dusting of fresh poured concrete surfaces with cement or a cement and sand mixture before or during the finishing operations will not be permitted.

All external corners shall have a nominal 20mm x 20mm chamfer unless specifically excluded on the drawings.

12.4.2 Formed Surfaces - Classes of Finish

Finishes to formed surfaces of concrete shall conform to the following:

a. AS 3610 Class 3 - Surfaces permanently exposed to view or in contact with water.

b. AS 3610 Class 5 - All buried surfaces.

12.4.3 Pier, Foundation and Wall Top Finishes

Unless otherwise specified or shown on the drawings, the tops of all building piers which are to receive steel and the tops of all other footings, such as the equipment footings, which will be grouted later, shall be left 30mm below the bottom of the base plate. Grouting shall only take place after steel or equipment is set in position.

The top surface on which grout is to be placed shall be finished with a steel trowel, true to line and level.

The tops of all concrete walls shall be given a metal float finish.

For further details refer to CSBP Engineering Standard Grouting (ES-14-202-14).

Concrete

ES-14-202-10



12.4.4 Building Floor and Exterior Slab Finishes

a. All footpaths, roadways and storage slabs shall have a broomed finish and formed sides. Side and joint edges shall be finished with a 50mm edging and jointing tool with a 3mm radius.

b. Sub-floors, which will subsequently be covered with vinyl tile industrial asphalt tile or ceramic tile shall be given a light, smooth, steel trowel finish.

c. Architectural building floor slabs finished to final grade shall have a hard steel trowel finish unless specified otherwise on the Drawings.

d. Bunded grade slabs for the purpose of process liquor containment shall be trowelled by mechanical means to provide a dense, compacted, non-slip surface. Slab areas exposed to corrosive liquors and requiring subsequent application of surface protection are not included in this Section.

e. Slab areas that are to receive subsequent application of a surface protection system shall be floated and steel trowelled to produce a uniform, tight surface meeting flatness tolerances.

12.5 CURING

Curing of all concrete shall be carried out with the use of water or with an approved curing compound applied strictly in accordance with the manufacturer’s recommendations. Refer to Section 6.7 for curing compound products.

If water is used, the concrete shall be protected from premature drying out by wetting the surface to keep it continuously moist for a period of seven days after placing.

Sheet materials may be used on slabs for curing, provided the sheet laps are sealed and the sheet is kept in place for not less than seven days.

12.5.1 Curing Compounds

Curing compound shall be applied immediately following finishing of slabs or stripping of formed surfaces. (See also ‘Hot Weather Requirements’, Section 12.6). As soon as a slab surface has hardened sufficiently that it will not be marred by the application, the curing compound shall be applied. If the surface of the slab has dried out prior to the application it shall be saturated with water before the curing compound is applied, but there shall be no free water on the surface at the time of application. Prior to the application of curing compound, formed surfaces shall be sprayed with water after the forms are stripped, or soaked with water for twenty-four (24) hours if the forms have been on for over twenty-four (24) hours.

Note: Curing compounds shall not be used on any construction joints or on any other surfaces to which it is intended to later bond joint sealer or additional concrete, or to apply liquid surface hardener, membrane water proofing, built-up roofing, paint, wood block, floor tile adhesive or other adhesive coating.

Concrete

ES-14-202-10



12.6 HOT WEATHER REQUIREMENTS

The Contractor shall have all necessary materials and equipment on the job site, ready for use whenever concreting during predictably hot periods of the year to protect concrete from damaging high temperatures. Procedural requirements are as follows:

a. Concrete shall not be placed without specific approval of the Superintendent when the predicted shade temperature during the concreting operation (including finishing) will exceed 32°C.

b. The temperature of the concrete when placed shall not be higher than 26°C. Aggregate and mixing water shall be cooled (using ice, if necessary) to prevent the high temperature of the concrete mix from exceeding this limit.

As an alternative, the Superintendent may consider the use of blended cements to reduce concrete temperatures. The Contractor shall submit such proposals in writing at least forty-eight (48) hours prior to the application of concrete.

c. For hot weather concreting, particularly on windy days when the evaporation rate exceeds 0.5kg per square metre per hour and where there is a risk of plastic shrinkage cracking, an approved aliphatic alcohol evaporation barrier shall be applied after every finishing operation.

d. Forms and reinforcing shall be sprayed with water to reduce the temperature and excessive drying. The sub-grade shall be thoroughly dampened just prior to concrete placing, but not to cause water to form into pools. Care shall be taken with spraying water in those areas where concrete bonding agents are being used. If bonding agents become affected by water, they shall be replaced to the Superintendent’s satisfaction before concrete pour operations commence.

e. After twenty-four (24) hours of moist curing, curing shall be continued by application of water for a period of seven consecutive days after placing of the concrete, or while the concrete surfaces are still moist, curing compound shall be applied. If these precautions are not sufficient to prevent plastic shrinkage cracking, the placing of concrete may be restricted to late evening or night. The temperature of water used for moist curing shall be similar to the temperature of the concrete to avoid cracking.

f. The Contractor shall submit a method statement detailing special curing techniques for any continuous concrete pours over 2 hours duration and for slabs or footings exceeding 50 cubic metres or 0.5m deep, to the Superintendent for approval prior to commencing the pour.

g. The Superintendent may consider the use of a retarding agent or superplasticiser to reduce detrimental effects.

Concrete

ES-14-202-10



12.7 BLINDING CONCRETE

The Contractor shall place 50mm of blinding concrete to the underside of all major footings (whether indicated on the drawings or otherwise) unless it can be demonstrated to the Superintendent that the reinforcement can be adequately supported, cover requirements met, and the excavation kept clean and dry without blinding.

Blinding concrete need not be vibrated or screeded but shall be worked with shovels to minimise trapped air and obtain a satisfactory working base.

12.8 PUMPED CONCRETE

Approval to use pumped concrete may be given by the Superintendent subject to the Contractor submitting full details of:

• type and capacity of the pumps;

• pipework and procedures to be adopted;

• satisfactory evidence that any modifications to the concrete proportions and consistency, to suit pumping procedures, shall comply with the provisions and intent of this Standard.

12.8.1 Equipment Requirements

The pump shall have a variable speed control and shall be capable of pumping concrete containing 20mm aggregate through delivery lines not less than 75mm diameter.

Delivery lines shall be of an approved type. Under no circumstances shall aluminium alloy pipes and fittings be used, or concrete to come in contact with aluminium during its manufacture, transport or placing. The delivery lines shall not exceed 80m in length without specific approval from the Superintendent.

12.8.2 Procedural Requirements

a. Direct efficient communication shall be maintained at all times between the pump operator and the concrete placing crew.

b. Where delivery lines are exposed to the hot sun they shall be protected by covering with bags, wet hessian or other approved means.

c. During delays in delivery of concrete to pump, concrete in the lines shall be pumped at approximately 10 minute intervals (5 minutes in hot weather) to ensure that the concrete is ‘live’. For piston type pumps at least two strokes of the piston shall be made at each pumping interval.

d. In the event of any delay or breakdown in the equipment not exceeding 20 minutes during which time concrete cannot be placed, the concrete already in place shall have ‘wet edges’ maintained in an approved manner.

e. Should the atmospheric (shade) temperature on the Site not exceed 18°C, the concrete in the receiving hopper and lines may be placed in the work on the resumption of pumping, when approved by the Superintendent.

Concrete

ES-14-202-10



f. Should the temperature exceed 30°C, the receiving hopper and lines shall be cleaned out and the concrete contained therein discarded.

g. If the delay exceeds twenty minutes an emergency construction joint shall be formed where directed, the concrete completed to the construction joint and all concrete in the pipeline shall be discarded.

h. Where the temperature lies between 18°C and 30°C, the decision as to whether to use or discard the concrete shall be determined by the Superintendent. The Superintendent’s representative will record details of the Superintendent’s decision specifying date, time and location of concrete.

12.9 DEFECTS IN FORMED SURFACES

If any defects are revealed after removal of formwork, they shall be rectified to the satisfaction of the Superintendent as follows:

a. Fins, pinhole bubbles, surface discolouration and minor defects may be rubbed down with sacking immediately the formwork is removed.

b. Abrupt and gradual irregularities may be rubbed down with Carborundum and water after the concrete has been fully cured.

c. Any other defects shall be remedied by methods approved by the Superintendent.

12.10 HOLES TO BE FILLED

Recesses resulting from the removal of form ties, shall be thoroughly cleaned and saturated with water then filled with mortar in the proportion of one part of cement to three of sand and floated flush. If the finished surface is deemed unsatisfactory by the Superintendent, further treatment shall be carried out using the mortar specified above and rubbing down with a medium course carborundum stone until a surface is produced which is clean, smooth and consistent with the class of surface finish required. Mortar patches shall be either kept moist for seven days or sprayed with curing compound immediately after patching is completed.

Concrete

ES-14-202-10



13. TESTING

13.1 GENERAL

The Contractor’s testing responsibilities shall include preliminary concrete testing, and all tests required under Section 4.0, except where concrete is CSBP supplied in accordance with Section 7.0. Unless concrete is CSBP supplied, testing of concrete shall be performed as required by AS3600 Section 20 and AS1379. Test results shall be forwarded to the Superintendent.

The Contractor shall take test cylinders during the process of the work for determining the time for form stripping or where a structure may be required to be put into use. These tests shall be in addition to those required above. The test cylinders shall be field cured.

In the event that the concrete tested in accordance with the requirements of AS1379 fails to meet the strength requirements of those specifications, the Superintendent may require core testing of the cast-in-place concrete in accordance with AS1012, Part 14. The tests will be at the Contractor’s expense unless the results show 100 per cent or more of the specified twenty-eight-- (28) day compressive strength.

The Superintendent, at the expense of the Contractor, may reject any concrete failing to comply with these specifications.

13.2 PROJECT CONTROL TESTING

The Contractor shall be responsible for all costs associated with project control testing by a NATA registered laboratory as specified, except where concrete is CSBP supplied in accordance with Section 7.0. Testing of concrete shall be performed as required by AS3600 Section 20 and test results forwarded to the Superintendent.

concrete

Documents

concrete es

review of document

concrete number

steel reinforcement

controlled document

version number

concrete materials

concrete strength