25652-2000-3PS-S000-C0001-Att001r002v3_0

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Abu Dhabi Oil Refining Company

STRUCTURAL ENGINEERING DESIGN CRITERIADGS-CU-002

Rev-2 Mar 2009

Takreer DGS-CU-002-Rev-2 Mar-2009 (Without Addm sheet) Initials Page 2 of 27

Table of Contents

1.0 GENERAL .............................................................................................................................. 3 2.0 CODES AND STANDARDS.................................................................................................... 3 3.0 REFERENCE DOCUMENTS ................................................................................................. 7 4.0 DOCUMENT PRECEDENCE................................................................................................. 7 5.0 SPECIFICATION DEVIATION/CONCESSION CONTROL..................................................... 8 6.0 QUALITY ASSURANCE/QUALITY CONTROL ...................................................................... 8 7.0 DESIGN.................................................................................................................................. 8 8.0

LOAD COMBINATIONS ....................................................................................................... 19

9.0 DEFLECTION....................................................................................................................... 22 10.0 STRUCTURAL STEEL......................................................................................................... 22 11.0 CONCRETE ......................................................................................................................... 25 12.0 MASONRY ........................................................................................................................... 25 13.0 FIREPROOFING.................................................................................................................. 26 14.0 FOUNDATIONS ................................................................................................................... 26 15.0 ALLOWABLE STRESSES ................................................................................................... 26 16.0 STABILITY CHECKS............................................................................................................ 26

List of Authorized Signatures/ Initials

DGS Discipline Committee Member, ADRD ------------------------------

DGS Discipline Committee Member, RRD ------------------------------

DGS Discipline Committee Member, E&PD Faran Khurshid (FK)

DGS Discipline Committee Member Leader, E&PD Adham Barakat (AB)

Engineering & Technical Services Manager, E&PD Quazi Abdul Matin (QAM)

Engineering & Projects Division Manager, E&PD Mohamed Al Yabhouni (MAY)

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1.0 GENERAL

1.1 SCOPE

This specification establishes the minimum criteria for structural engineering and designon this Project.

1.2 PURPOSE

This specification contains the minimum criteria for structural engineering and design of allbuildings and other structures for the supporting of vessels, columns, machinery, stacks,tanks, piping, etc. These minimum requirements are also applicable to special structuressuch as jetties, platforms, etc. However, these special structures in general will be subjectto additional requirements specified separately.

1.3 DEFINITIONS

For the purpose of this specification, the following definitions shall apply:

COMPANY – The Abu Dhabi Oil Refining Company (TAKREER)

CONCESSION REQUEST – A deviation requested by the CONTRACTOR usually afterreceiving the contract package or purchase order. Often, it refers to an authorization touse, repair, recondition, reclaim, or release materials, components or equipment already inprogress or completely manufactured by which does not meet or comply with COMPANYrequirements. A CONCESSION Request is subject to COMPANY approval.

CONTRACTOR - The party which carries out all or part of the design, engineering, pro-curement, construction, commissioning or management of the Project.

MANUFACTURER – The service organisation which actually manufactures the material /product

CONTRACT DOCUMENTS – The complete set of documents, including specifications anddrawings, that defines the specific obligations and rights of the parties involved in the ac-complishment of the work covered by this Specification.

SHALL — Indicates a mandatory requirement.

SHOULD — Use of the word “should” indicates a strong recommendation to comply withthe requirements of this document.

2.0 CODES AND STANDARDS

It shall be the CONTRACTOR’S and its CONSULTANT’S and /or SUBCONTRACTOR’Sresponsibility to be, or to become, knowledgeable of the requirements of the referencedCodes and Standards.

Where there are conflicts between the requirements of different Codes andStandards the most stringent criteria shall apply, subject to approval of the COMPANY.

Alternate codes and standards meeting the requirements of the referenced standardsand codes may be used with approval of the COMPANY

The following Codes and Standards, to the extent specified herein, form a part of thisspecification. When an edition date is not indicated for a Code or Standard, the latest edi-tion in force at the time of Contract award shall apply.

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Where this specification differs with the referenced Project Specifications or Codes and

Standards, this specification shall govern.2.1 CODES

AASHTO (American Association of State Highway and Transportation Officials):

AASHTO-LRFD -Standard Specification for Highway Bridges

ACI (American Concrete Insti tu te):

ACI 318M Building Code Requirements for Structural Concrete With Commentary

ACI 350M/350RM Metric Code Requirements for Environmental Engineering ConcreteStructures and Commentary

AISC (American Inst itute of Steel Const ruct ion):

AISC Steel Construction Manual 13th Edition

AISC Specification for Structural Steel Buildings

The AISC Code of Standard Practice for Steel Buildings and Bridges

The AISC Specification for Structural Joints Using ASTM A325 or A490 Bolts

AISI(American Iron and Steel Insti tu te)

AISI 67 1/2 Specification and Commentary for the Design of Cold Formed Steel Struc-tural Members

ANSI(Amer ican National Standards Insti tu te)

ANSI A14.3 : Safety Requirement for Fixed Ladders.

ANSI A1264.1 : Safety Requirements for Workplace Floor and Wall Openings, Staircase& Railing System

API (American Petroleum Inst itute):

API 650 Welded Steel Tanks for Oil Storage (Seismic Design)

ASCE (American Society of Civ il Engineers):

ASCE 7 Minimum Design Loads for Buildings and Other Structures

ASCE Task Committee Report on Design of Blast Resistant Buildings in PetrochemicalFacilities

ASCE Task Committee Report on Wind Loads and Anchor Bolt Design in PetrochemicalFacilities

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ASCE Task Committee Guidelines for Seismic Evaluation and Design of Petrochemical

Facilities

ASNT (American Society for Nondest ruct ive Test ing):

ASNT-TC-1A Recommended Practice

AWS (American Welding Society):

AWS D1.1 / D1.1M Structural Welding Code

AWS D1.4 / D1.4M Structural Welding Code - Reinforcing Steel

ICBO (International Conference of Building Officials)

UBC Uniform Building Code, Structural Engineering Design Provisions

2.2 STANDARDS

ASTM (American Society for Testing and Materials):

A 36/A 36M Standard Specification for Structural Steel

A 53/A 53M Standard Specification for Pipe, Steel, Black and Hot-Dipped Zinc-Coated Welded and Seamless

A 123/A 123M Specification for Zinc (Hot-Dip Galvanized) coatings on Iron & Steelproducts

A 143/A 143M Standard Practice for Safeguarding Against Embrittlement of Hot-DipGalvanized Structural Steel Products and Procedure for DetectingEmbrittlement

A 185/A 185M Standard Specification for Welded Steel Wire Fabric, Plain, for Con-crete Reinforcement

A 307 Standard Specification for Carbon Steel Bolts and Studs, 60,000 psiTensile Strength

A 325M Standard Specification for Structural Bolts, Steel, Heat Treated, 830MPa Minimum Tensile Strength (Metric)

A 490M Standard Specification for High Strength Steel Bolts, Classes 10.9& 10.9.3, for Structural Steel Joints (Metric)

A 500 Standard Specification for Cold-Formed Welded and Seamless Car-bon Steel Structural Tubing in Rounds and Shapes

A 563M Standard Specification for Carbon and Alloy Steel Nuts (Metric)

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A 572/A 572M Standard Specification for High-Strength Low-Alloy Columbium-

Vanadium Structural Steel

A 1011/ A 1011M Standard Specification for Steel, Sheet and Strip, Hot-Rolled, Car-bon, Structural, High-Strength Low-Alloy and High-Strength Low Al-loy with Improved Formability & Ultra-High Strength

A 615/A 615M Standard Specification for Deformed and Plain Billet-Steel Bars forConcrete Reinforcement

A 786/A 786M Standard Specification for Rolled Steel Floor Plates

C 55 Standard Specification for Concrete Building Brick

C 90 Standard Specification for Loadbearing Concrete Masonry Units

C 270 Standard Specification for Mortar for Unit Masonry

C 1314 Standard Test Method for Compressive Strength of Masonry Prisms

F 436 Standard Specification for Hardened Steel Washers

BSI (British Standards Institution):

BS 4449 Carbon Steel Bars for the Reinforcement of Concrete

BS 4-1 Structural Steel Section Part 1, Specification for Hot Rolled Sections

BS 4483 Specification for Steel Fabric for the Reinforcement of Concrete

BSEN 10210-2 Hot- Finished Structural Hollow Sections of Non-Alloy & Fine GrainSteels Part 2: Tolerances, Dimensions & Sectional Properties

BS 4592 Industrial Type Metal Flooring, Walkways and Stair Treads

BS 5950 Structural Use of Steel work in Building

BS 7419 Holding Down Bolts

BS 8004 Foundations

BS 8007 Design of Concrete Structures for Retaining Aqueous Liquids

BS 8110 Structural Use of Concrete

ISO (International Organization for Standardization):

ISO 9001-2000 Quality Management Systems - Requirements

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ISO 9004-2000 Quality Management Systems - Guidelines for Performance Im-

provements

ISO 19011 Guidelines for Quality and/or Environmental System Auditing

SJI (Steel Joist Institute):

42nd Catalogue of Standard Specifications and Load Tables for Steel Joists and JoistGirders

3.0 REFERENCE DOCUMENTS

Project Specifications:

DGS-AU-051 Design General Specification -Concrete (Buildings)

DGS-AU-100 Design General Specification- Architectural Engineering Design Crite-ria

DGS-CU-001 Design General Specification-Civil Engineering Design Criteria

DGS-CU-011 Design General Specification-Grouting

DGS-CU-012 Design General Specification-Fireproofing Requirements

DGS-CU-013 Design General Specification-Concrete Design

DGS-CU-014 Design General Specification-Concrete Mix Design

DGS-CU-020 Design General Specification-Structural Steel Fabrication

DGS-CU-021 Design General Specification-Structural Steel Erection

DGS-CU-032 Design General Specification-Geotechnical Investigation

DGS-MX-002 Design General Specification-Galvanizing

4.0 DOCUMENT PRECEDENCE

The CONTRACTOR shall notify the COMPANY of any apparent conflict between thisspecification, the related drawings, the Codes and Standards and any other specifications

noted herein. Resolution and/or interpretation shall be obtained from the COMPANY inwriting before proceeding with the design manufacture.

In case of conflict, the order of precedence shall be as:

Design Drawings

Scope of Work, Engineering Narratives and Design Philosophies

Design General Specifications (DGS)

Standard Drawings

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Industry Codes and Standards

5.0 SPECIFICATION DEVIATION/CONCESSION CONTROL

Any technical deviations to this specification and its attachments shall be sought throughCONCESSION REQUEST format. CONCESSION REQUESTS require COMPANY’S re-view/approval, prior to the proposed technical changes being implemented. Technicalchanges implemented prior to COMPANY’S approval are subject to rejection.

6.0 QUALITY ASSURANCE/QUALITY CONTROL

CONTRACTOR’S proposed quality system shall fully satisfy all the elements of ISO 9001 -2000, “Quality Management Systems – Requirements” and ISO 9004 - 2000, “QualityManagement Systems – Guidelines for Performance Improvements” . The quality systemshall provide for the planned and systematic control of all quality-related activities per-formed during design, development, production, installation, or servicing (as appropriate to

the given system).

Implementation of the system shall be in accordance with the CONTRACTOR’S QualityManual and Project Specific Quality Plan, which shall both together with all re-lated/referenced procedures, be submitted to COMPANY for review, comment and ap-proval as required by purchase/contract documents.

7.0 DESIGN

Structural design criteria shall be as follows:

a. Steel structures design shall be governed by the AISC “Steel Construction Manual –13th Edition”, “Specification for Structural Steel Buildings” and the “Code of StandardPractice for Steel Buildings and Bridges”. The Allowable Stress Design (ASD)method shall be implemented except for elements designed for blast resistancewhere provisions of ASCE Blast Design Report shall govern. The plastic designmethod in AISC shall NOT be used in Steel Design.

b. Concrete design shall be governed by ACI , Standard Building Code Requirementsfor Structural Concrete ACI318M and other Codes and Specification referencedherein.

c. Structural steel joint design shall satisfy the requirements of AISC Specification forStructural Joints using ASTM A 325M or A 490M bolts

d. Steel joists shall be governed by the SJI (Steel Joint Institute) 42nd Edition Cata-logue of Standard Specifications and Load Tables for Steel Joists and Joist Girders

The following Primary Loads and forces shall be considered in the design of plant struc-

tures. The various combinations of these loads to be used in design calculations are givenin Section 8.0.

7.1 DEAD LOAD

Dead loads shall be the total weight of materials forming the permanent part of a structure,empty vessels and equipment, built-in partitions, fireproofing, insulation, empty piping,electrical conduit, and other permanent fixtures.

Self weight of the structure shall be included as dead load.

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Weight of equipment shall be derived as far as possible from the manufacturer’s data and

shall include instrumentation and controls, appurtenances, auxiliary components, machin-ery, and piping.

7.2 OPERATING LOAD

Operating loads shall be defined as the weight of any liquids or solids present within thevessels, equipment, or piping during normal operation. Unusual loading that occurs duringregeneration or upset conditions shall also be considered. Operating loads shall have thesame load factor as dead load.

7.3 TEST LOAD

Test loads shall be defined as the weight of any liquid necessary to pressure-test vessels,equipment, or piping. Test loads shall have the same load factor as dead load.

7.4 LIVE LOAD

Live loads shall be defined as the weight of all movable loads including personnel, tools,miscellaneous equipment, movable partitions, cranes, hoists, parts of dismantled equip-ment and stored material.

Minimum Live loads shall be as specified below:

Category Uniform Load ConcentratedLoad

Storage areas

Loads to be determined from proposeduse, but never less than noted

7.0 KN/m2 None

Operating areas and platforms 5.0 KN/m2 5.0 KN

Personnel access and inspection plat-forms and walkways

2.0 KN/m2 3.0 KN

Stairs and ramps 5.0 KN/m2 5.0 KN

Roofs accessible for inspection and repair 1.0 KN/m2 2.0 KN for roofmembers

Offices, first-aid buildings, guard houses,toilets, wash and locker rooms, analyzer

houses, control rooms, computer rooms,instrument auxiliary rooms, electricalequipment rooms, laboratory rooms

3.0 KN/m2

Canteens, lunchrooms, training centers,corridors, and halls

5.0 KN/m2

Library and filing rooms 7.2 KN/m2

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Category Uniform Load ConcentratedLoad

Battery rooms, simulator rooms in trainingcenter

10.0 KN/m2

Mechanical, electrical, instrument work-shop building (inclusive of covered area),workshop area in training center, and con-sumables store

12.0* KN/m2

Bulk store 12.0**

KN/m2

* Live Load includes small equipment. Use actual equipment load when larger in effectthan uniform

** Minimum bulk storage load. Bulk storage Live Loads shall be confirmed on a case bycase basis

Railing and handrails shall be designed for a minimum concentrated load of 1.0 KNapplied horizontally at any point in any direction on the top rail

Platforms where heavy maintenance may occur shall be designed for a minimumuniform live load of 7 KN/m2 or a minimum moving concentrated load of 5 KN

Uniform loads and concentrated loads do not occur simultaneously

Concentrated loads shall be assumed uniformly distributed on any square spacewith 0.75 m side length (0.5625m2)

7.5 TRUCK LOAD

7.5.1 Bridges, trenches, and underground installations accessible to truck loading shall be de-signed to withstand HS20-44 loading as defined by AASHTO Standard Specifications forHighway Bridges. Maintenance or construction crane loads shall also be considered. Mo-bile crane loads shall be the greater of either, moving wheel loads plus impact or themaximum outriggers reaction at full lifting capacity. Maximum horizontal loads caused bybraking or acceleration shall be considered as applicable. For the design of each struc-tural element the most unfavorable position of the crane or other moving loads shall beconsidered. For moving loads an appropriate impact factor shall be applied. Truck orcrane loads shall have the same load factor as live loads.

7.5.2 At least one road leading to the main process area(s) shall be designated as a heavy

equipment route and bridges/culverts including other underground facilities shall be de-signed for the maximum expected loading condition caused by transportation of heavyequipment.

Spread of wheel loading through any fill, lesser than 0.9m thick, above thebridge/culvert shall not be assumed in design.

7.6 WIND LOAD

7.6.1 Wind loads shall be in accordance with ASCE 7

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7.6.2 Basic wind speed of a 3 second gust at standard height of 10 m above ground shall be

160 km/h7.6.3 Wind loads are based on terrain Exposure “C” and topographic factor, Kzt = 1.0

7.6.4 Importance factors, I = 1.0 for all structures

I = 1.15 for Substations, Satellite Instrument Shelters, Control Buildings, Fire buildingsand Firewater Pump Shelters

7.6.5 The following shape increase factors may be used to modify the projected areas of verticaland horizontal vessels (including insulation, if any) to allow for attachments such as man-holes, nozzles, piping, ladders, and platforms. For computation of wind loads on roundshaped vessels use Cf = 0.8 unless higher values are specified in ASCE 7

Vessel Diameter (m) Increase Factor

0.5 - 1.0 1.6

1.0 - 1.5 1.37

1.5 - 2.0 1.28

2.0 - 2.5 1.20

2.5 and up 1.18

Spherical (any dia.) 1.10

7.6.6 Wind loads shall be separately computed for all supported equipment, ladders, and stairsexcept for vessels where projected area increase factors have already accounted forthese items

7.6.7 Gust effect factors, G, for main wind resisting systems of flexible buildings, structures, andvertical vessels having a height exceeding five times the least horizontal dimension or afundamental natural frequency less than 1.0 Hz shall be calculated as described in ASCE7

7.6.8 No reduction shall be made for the shielding effect of vessels or structures adjacent to thestructure being designed

7.6.9 Wind and earthquake loads shall not be assumed to act concurrently

7.6.10 For Multi-Storied equipment supporting (process) structures, wind load shall be computed

on the full projected area perpendicular to wind of the occupied stories, considering aforce coefficient of 1.0. Alternatively, wind loads on individual areas of equipment, piping,appurtenances, structural elements etc… may be integrated after considering the forcecoefficient corresponding to each area

7.6.11 For overhead pipe racks of 4 m wide or less, the wind load on the three largest pipes shallbe taken into account. For overhead pipe racks of over 4 m wide, the wind load on the fourlargest pipes shall be taken into account. For computation of wind loads on piping, a force

coefficient, Cf = 0.8 shall be considered unless higher values are specified in ASCE 7.Wind loading on piping shall be computed as follows:

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For pipe racks 4m wide or less:

Wp = 0.8 qh (D1+D2+D3)

For pipe racks wider than 4m:

Wp = 0.8 qh (D1+D2+D3+D4)

Where:

Cf = Force Coefficient (0.8)

Wp = Unit design wind load on piping (N/m run of piping)

qh = Velocity pressure determined at piping elevation, h (N/m2)

Dn = Diameter of pipe plus insulation (m)

7.7 E ARTHQUAKE LOAD

7.7.1 Earthquake loads shall be defined as the horizontal and vertical forces equivalent in theirdesign effect to the loads induced by ground motion during an earthquake.

7.7.2 All plant equipment and structures shall be designed for earthquake loads in accordancewith the UBC and the following factors:

Seismic Zone 1 Z = 0.075

Importance Factor I = 1.0 for all structuresI = 1.25 for Control Buildings, Substa-tions, Satellite Instrument Shelters,Firewater Pump Shelters and FireBuilding

Soil Profile Type per UBC classification (based on thesoil investigation report)

7.7.3 Seismic design for storage tanks at grade shall be in accordance with API 650, WeldedSteel Tanks for Oil Storage and the following factors:

Seismic Zone 1 factor, Z 0.075

Importance Factor, I 1.0

Lateral force coefficient, C1 0.60

Lateral force coefficient, C2 (to be calculated)

Site Coefficient, S Per API 650 Classification (based onthe soil investigation report)

7.7.4 Computed seismic loading is an ultimate limit by definition. The computed seismic loadmagnitude shall be scaled by the relevant factors of ASCE 7 before inclusion in serviceload combinations

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7.8 CRANE/IMPACT LOAD

For structures carrying dynamic impact-inducing equipment and/or live loads, the loadshall be increased, if not otherwise specified by the equipment manufacturer, with the fol-lowing dynamic impact factors:

CategoryVerticalLoad

HorizontalLoad

For supports of elevators (dead and live load) 100%

Cab operated traveling crane support girders3 andtheir connections

25% 20%1

10%2

Pendant operated traveling crane support girders3 and their connections

10%

Monorails, trolley beams, davits 50%4

Light machinery, shaft or motor driven 20%

Reciprocating machinery or power driven units 50%

Hangers supporting floors, overhangs and balco-nies

33%

Lifting lugs or pad eyes 100%4

NOTES:

(1) Horizontal surge load as percent of the sum of the crane rated capacity plusweights of the crane trolley, cab and hooks. Apply one-half of the load at the top ofeach rail, acting in either direction, normal to the runaway rails

(2) The longitudinal braking force shall, if not otherwise specified by the manufacturer,be taken as 10% of the maximum wheel loads of the crane applied at the top of therail

(3) Live load on crane support girders shall be taken as the maximum wheel loads

(4) Applied to the maximum lifted weight

7.9 DYNAMIC LOAD

7.9.1 Dynamic loads shall be defined as forces caused by vibrating machinery such as pumps,turbo-machinery, generators, blowers, fans, and compressors. Included within this defini-tion are surge forces similar to those acting in fluid cokers, hydroformers, and crackers.

Centrifugal pump foundations for pumps less than both 750 kW and 2.0 tons mass do notrequire a dynamic analysis. However, the foundation to pump assembly weight ratio shallnot be less than 3 to 1.

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Foundations for reciprocating machinery, centrifugal machinery, and centrifugal pumps

over 750 kW or 2.0 tons mass require a three dimensional dynamic analysis. For suchequipment, foundation to machine weight ratio shall not be less than 5 to 1.

7.9.2 When required, a three dimensional dynamic analysis for rotating equipment foundationsshall be performed and shall show that the dynamic amplitudes will not exceed the lowerof the following values:

7.9.2.1 The maximum allowable values stated by the manufacturer of the equipment

7.9.2.2 The amplitude (single amplitude) which causes the effective velocity of vibration to exceed(see Figure 1):

2 mm/s at the location of the machinery-bearing housing

2.5 mm/s at any location of the structure

NOTE: The effective velocity, or RMS velocity, is defined as the square root of the aver-age of the square of the velocities, velocity being a function of time. In the caseof a pure sinusoidal function, the effective velocity is 0.707 times the peak valueof the velocity

7.9.2.3 The dynamic amplitudes of any part of the foundation including any reciprocating com-

pressor shall be less than 80 m (80 x 10-3 mm) single amplitude.

7.9.3 For the dynamic analysis, the exciting forces shall be taken as the maximum values that,according to the manufacturer of the equipment, will occur during the lifetime of theequipment. When the exciting force is not given by the manufacturer, it shall be deter-mined from

Q (KN) = [Rotor Speed (rpm)/6000] x Rotor Weight (KN)

7.9.4 The dynamic calculations shall be based on a mechanical model wherein the masses,damping, stiffness and elasticity of both structure and foundation and mass of the equip-ment are represented in an appropriate way.

7.9.5 All natural frequencies below 2 times the operating frequency for reciprocating equipmentand below 1.5 times the operating frequency for rotating equipment shall be calculated.

7.9.6 It shall be demonstrated that the amplitude of the natural frequencies between 0.35 and1.5 times the operating frequency are within the allowable values even assuming that -due to differences between the actual structure and the assumed model - resonance doesoccur. In this case, a reasonable amount of damping should be estimated.

The natural frequency of the supporting structure shall not coincide with any resonant fre-quency of the equipment.

7.9.7 The static deformation for rotating equipment foundations shall be calculated and shownto be within the limits stated by the manufacturer of the equipment. The calculations shallinclude, but not be limited to, the following causes of deformation:

Shrinkage and creep of concrete

Temperature effects caused by radiation and convection of heat or cold generatedby machinery, piping, and ducting

Elastic deformation caused by changing vapor pressure in condensers

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Elastic deformation caused by soil settlement of elastic compression of piles

7.10 THERMAL FORCES

Provisions shall be made for thermal forces arising from restrained dimensional changesdue to temperature changes, moisture expansion, shrinkage, creep, and similar effects.

7.10.1 Thermal load shall be defined as those forces caused by a change in temperature. Ther-mal load results from both operating and environmental conditions. Such forces shall in-clude those caused by vessel or piping expansion or contraction, and expansion or con-traction of structures.

7.10.2 Thermal loads and displacements caused by operating conditions shall be based on thedesign temperature of the item of equipment rather than the operating temperature.

7.10.3 Design atmospheric temperature ranges from a minimum of 5o C to a maximum of 50o C.

7.10.4 Low friction slide plates (Teflon) shall be used if the vessel operating condition weight isgreater than 45 KN at the sliding end. For preliminary design, the temperature drop of

1.9 C/mm from the bottom of shell to bottom of saddle may be assumed. The followingfriction coefficients shall be used for calculating frictional restraint due to temperaturechange or lateral loading on sliding surfaces:

Surface Friction Coefficient

Steel-to-Steel (not corroded) 0.30

Steel-to-Concrete 0.50

Teflon-to-Teflon

A straight line variation of 0.17 to 0.08 for bearingstresses from 0.0 N/mm2 to 0.7 N/mm2, respectively

Bearing stress greater than 0.7 N/mm2

0.17 to 0.08

0.08

Graphite-to-Graphite 0.15

7.10.5 For computing friction loads due to the effects of pipe expansion in pipe racks, use the fol-lowing friction coefficients:

Number of Lines on Support Friction Coefficient

1 - 3 0.3

4 - 6 0.2

7 or more 0.1

For a given support, if considering only larger lines and ignoring smaller lines results ingreater loads, these forces and associated friction coefficients shall be used instead ofconsidering all the lines.

7.10.6 Pipe rack anchor beams shall be designed for an arbitrary horizontal pipe anchor force of15KN acting at mid-span, unless more accurate anchor forces are obtained from piping

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stress analysis. The pipe anchor force(s) shall not be distributed to the foundations of the

anchor bent under consideration.Pipe anchor forces shall be transferred by longitudinal girders to braced bays. An arbitraryforce of 5 percent of the total pipe operating load per layer shall be taken into account,unless more accurate anchor forces are obtained from piping stress analysis. Theseforces shall be distributed to the foundations of the braced bay.

7.10.7 In addition to reactions from thermal forces, pipe rack longitudinal girders shall be de-signed for an arbitrary uniform operating vertical load of 2.5kN/m. This load shall not bedistributed to the foundations.

7.11 ERECTION LOAD

Erection loads are temporary forces caused by the installation or erection of equipment orstructures. Erection loads are considered in load combinations as live load.

Beams and floor slabs in multi-story structures e.g., fire decks, shall be designed to carrythe full construction loads imposed by the props supporting the structure immediatelyabove. A note shall be added on the relevant construction drawings to highlight theadopted design philosophy.

Heavy equipment lowered onto a supporting structure can introduce extreme point loadson structural members, exceeding any operating or test load. After placing of equipment,the exact positioning (lining out and leveling) can also introduce extreme point loads. Thispotential loading condition shall be considered in design calculations where appropriate.

7.12 M AINTENANCE LOAD

7.12.1 Maintenance loads are temporary forces caused by the dismantling, repair, or painting ofequipment. Maintenance loads, including Bundle Pulling Forces, shall be considered in

load combinations as live load.

7.12.2 The supports of heat exchangers shall be designed to withstand a longitudinal bundle pullforce of 200% of the bundle weight, unless the bundles are pulled by means of a me-chanical device which acts on the principle of equilibrium of forces.

7.13 DIFFERENTIAL SETTLEMENT

Provisions shall be made for forces arising from assumed differential settlements of foun-dations and from restrained dimensional changes due to temperature changes, moistureexpansion, shrinkage, creep, and similar effects. These loads are considered in load com-binations as dead load.

7.14 E ARTH AND W ATER PRESSURE

Earth and hydrostatic water pressures on retaining walls and underground structures shallbe determined. Outward pressures on liquid-retaining structures shall also be considered.Earth and water pressures are considered in load combinations as live load.

Concrete bund walls shall be designed for accidental load condition when the bund iscompletely filled with water to the crest. Only the hydrostatic fluid acting in the outward di-rection and gravity loading need to be considered. The factor of safety shall not be lessthan 1.3 for this loading condition.

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7.15 BLAST LOAD

Blast load design of plant buildings shall be based on building design philosophy and crite-ria defined in Project specifications and narratives elsewhere in the Contract documents.Blast load characteristics shall be obtained as specified in the next subsections.

7.15.1 QRA Based Blast Load

Dynamic Blast Load characteristics shall be determined from a dedicated QuantitativeRisk Assessment (QRA) of the building site. The following parameters are required fromthe QRA to define the blast load:

Blast side-on overpressure curve shape and peak magnitude Pso (kPa)

Blast duration td (milliseconds)

The above primary parameters shall be used as per methods of ASCE Task Committee

Report; “Design of Blast Resistant Buildings in Petrochemical Facilities”, to fully describethe blast load characteristics.

Buildings subjected to the above dynamic blast loading shall be analyzed and designed tomeet the ductility demand limits defined in the Project Building Design Criteria or Philoso-phy.

Where Blast Resilience is specified, concrete building framing shall be detailed to satisfythe requirements of ACI 318M Chapter 21 for Intermediate Moment Resisting Frames.Requirements of Special Moment Resisting Frame shall be implemented where buildingBlast Resistance is specified.

Alternatively, the following criteria may be implemented subject to COMPANY approval:

7.15.2 Negligible Blast

Buildings located more than 500m away from hydrocarbon processing equipment do notrequire special provisions with regards to explosion resistance. Building framing detailsshall satisfy the requirements of ACI 318M Chapter 21, “Special Provisions for SeismicDesign” for Intermediate Moment Resisting Frames.

7.15.3 Blast Resilient

Buildings within 200m to 500m distance shall be designed in accordance with the followingblast design concepts:

7.15.3.1 The building structure frame, roof, walls, bracing, and connections shall be designed insuch a manner that large plastic deformations of the major frame members and externalwall panels will be allowed to take place without causing partial or total building collapse.

7.15.3.2 Blast resilient concrete buildings shall be detailed in accordance with ACI 318M Chapter21, “Special Provisions for Seismic Design”. Building framing shall comply with SpecialMoment Resisting Frame provisions. No special explicit blast loading needs be applied inload cases or combinations

7.15.3.3 The building frame shall be either reinforced concrete or structural steel.

7.15.3.4 The building walls shall be constructed as precast or cast in-situ reinforced concrete mod-ules, fully grouted reinforced masonry, or a properly designed structural steel claddingsystem. Walls for these buildings shall be structurally isolated from the main moment re-

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sisting framing and shall not be used as main frame members or to provide structural sta-

bility and/or structural strength.7.15.3.5 Materials with a brittle behavior, such as masonry, shall not be used in such a way that

they have a strength function.

7.15.3.6 The building roofs shall be constructed of monolithic reinforced concrete or a properly de-signed structural steel roofing system. Loose light-weight concrete roof slabs or asbestoscement sheeting shall not be used. Gravel as a protection of roof finish, or loose tiles forwalkways on top of the roof finish, shall not be used.

7.15.3.7 For steel structures, structural steel bracing in the roof and walls shall be provided.

7.15.4 Blast Resistant

Building within 200m distance from hydrocarbon processing equipment shall be designedto withstand the anticipated blast effect. Structural elements shall be based on the follow-

ing (clauses 7.15.4.1 – 7.15.4.4) equivalent static loads acting perpendicularly to the sur-face. Lesser loads may be used, subject to prior COMPANY approval, provided that theycan be justified by a site-specific hazard assessment.

7.15.4.1 External walls 100 KN/m2, except loads on doors and windows which may be assumed tobe 30 KN/m2.

7.15.4.2 Blast load on the roof slab is dependent on the span between supports.

Static Blast Load Span

50 KN/m2 3 m

45 KN/m2 4 m

40 KN/m2 5 m

35 KN/m2 6 m

30 KN/m2 7 m

25 KN/m2 8 m and over

These loads shall act simultaneously on one wall and the roof. Blast load acts with appli-cable dead load.

7.15.4.3 Suction from blast loads shall be 50% of the loads listed in Section 7.15.4.2 of this specifi-cation. Suction loads shall be calculated on the walls and roof.

7.15.4.4 Suction loads shall act simultaneously on one wall and the roof and not in combinationwith the blast loads listed in Section 7.15.4.2 of this specification.

7.15.4.5 Pre-stressed concrete shall not be used. In general, special attention shall be paid to en-sure continuity and a minimum of local stress concentration. Adequate lapping of rein-forcement is required.

7.15.4.6 Blast resistant concrete structures framing shall be detailed in accordance to ACI 318M,“Special Provisions for Seismic Design" to satisfy Special Moment Resisting Frames pro-visions except for the following:

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7.15.4.6.1 Concrete walls and slabs shall be reinforced each side in the main direction with a mini-

mum percentage of steel bars equivalent to 1.7/fy, where fy is the yield strength of thesteel bars.

In the other direction on both sides, a distribution reinforcement of at least 20% of that inthe main direction shall be applied. Maximum spacing of bars shall be 150 mm center tocenter. It is preferable for the wall and roof thickness to be between the limits of 250 and400 mm in order to facilitate the placing of the required reinforcing bars.

7.15.4.6.2 Shear reinforcement shall be applied in beams only and shall be a combination of stirrupsand horizontal side bars web reinforcement.

When the actual shear stress (V) is less than 1.3 N/mm2 (Vc1): no web reinforcement is re-quired.

When the actual shear stress (V) is more than 1.3 N/mm2 (Vc1), but less than 4.5 N/mm2

(Vc2): web reinforcement shall be required for (V-Vc1) N/mm2.Where:

V = Actual shear stress

Vc1 = Concrete shear stress lower limit

Vc2 = Concrete shear stress upper limit

At least 50 percent of the bottom main reinforcement shall extend over the face of thesupport providing a good anchorage between the supports.

7.15.5 Wind or earthquake loads shall not be combined with blast loads.

7.15.6 A load factor of 1.0 shall be used for all loads when combined with blast load.

7.15.7 Blast loads need not be taken into account for walls or foundations below ground level.7.15.8 Under blast conditions a maximum allowable soil bearing pressure equal to 75% of the

ultimate static bearing capacity may be used.

7.15.9 The foundation shall be designed so that the safety factor against overturning due to theunbalanced lateral reactions in not less than 1.2 under the load combination of dead plusblast loads.

7.15.10 Passive resistance of the foundation, where required in addition to the friction to resist slid-ing, shall be at least 1.5 times the unbalanced lateral load under the load combination ofdead plus blast loads. The unbalanced lateral load is defined as the total horizontal reac-tion force less the frictional resistance.

7.15.11 Individual foundations shall be tied together by tie beams to preserve the foundation sys-

tem integrity7.15.12 The structure shall be firmly embedded in the ground by having the foundations at least

1.5 m below grade, and having the same strength walls and columns below and abovegrade.

8.0 LOAD COMBINATIONS

8.1 Piles, structures and members of structures as well as their support and fixing points shallbe designed for the various loading combinations given in the following tables:

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Load Description Abbr. Ref. Section

Weight of Structure DL 7.1

Empty Weight of Vessels and Equipment DLempty 7.1

Operating Load DLop 7.2

Hydrostatic Test Load Test 7.3

Live Load LL 7.4

Moving/Truck Load LLmove 7.5

Wind Load WL 7.6

Earthquake Load EQ 7.7

Crane/Impact Load CR 7.8

Dynamic Load DY 7.9

Thermal Load TL 7.10

Erection Load ER 7.11

Maintenance Load ML 7.12

Differential Settlement DS 7.13

Earth/Water Pressure HY 7.14

Blast Load BL 7.15

8.2 Loads shall be combined as specified below.

Primary Load cases shall be combined using ASCE 7 load factors for allowable stress orstrength design methods as applicable.

Foundations and reinforced concrete buildings and structures shall be designed using the

Strength Design Method Load Combinations with due regard to serviceability limit statesusing Allowable Stress Design Load Combinations.

Structural steel, masonry, roofing, cladding, siding, railing and similar metallic structuresshall be designed using the Allowable Stress Design Load Combinations.

Basic Load Combinations A through G6 shall be investigated considering possible varia-tions of the participating Primary Load Cases and their corresponding load factors:

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LOAD COMBINATION

Operation Test Erec-tion

Earth-quake

Mainte-nance

Blast5 Primary

LoadsWithout

windWithwind

A B C D E F G

DL X X X X X X X

DLempty X X1 X X X X X

Test X

LL X X X X X X

CR X X X X

DLop X X1 X

LLmove X X X X

WL X X3,4

X4

EQ X

DY X X X2 X

TL X X X

ER X

ML X

DS X X X X X

HY X X X X X X

BL X

NOTES:

(1) The most unfavorable load combination shall be taken into account.

(2) Only if the structure supports rotating equipment that will be in operation while avessel is being tested with water.

(3) Only 50 percent wind load shall be taken into account.

(4) The effect of wind forces acting on temporary scaffolding erected during construction, orlater for maintenance, which will be transferred to the vessel or column shall be consid-ered. When considering these effects, the actual projected area of the scaffold mem-bers together with the correct shape factor and drag coefficient should be used. As aninitial approximation, the overall width of the scaffolding itself can be taken as 1.5 m oneach side of the vessel or column with 50 percent closed surface and shape factor 1.0.

(5) Blast condition shall be taken into account for the blast resistant design of buildingswhere applicable.

(6) In the ultimate limit state design, due regard shall be given to the different load factors for thevarious load combinations and the adverse or beneficial effects of the basic load cases.

(7) Where imposed loads (live loads) have a beneficial effect, they shall be zero.

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9.0 DEFLECTION

9.1 Deflections shall be calculated for dead load and live load with either operation/serviceloads or test load for the vertical direction, and for dead and live loads with opera-tion/service loads and 100 percent wind or seismic for the horizontal direction.

9.2 The following deflection limitations shall be used for design:

Beams (with effective span L):

Supporting beams L/3001

Crane runway beams (vertical) L/600

Crane runway beams (horizontal) L/500

Roof purlins L/400

Cantilevered beams (overhang) L/2401

(1) Including long term deflection of concrete beams

9.3 The following drift limitations shall be used for design:

Storey, structure or building (with height H):

Overall piperack drift H/300

Relative storey drift of multi-levelpiperack (H = storey height)

H/200

Portal frame columns H/200

Portal frame with overhead bridgecrane

H/500

Relative storey drift of equipmentsupporting structure (H = storeyheight)

H/240

Overall drift of multi-level equipmentsupporting structure

H/300

Overall building drift H/300

10.0 STRUCTURAL STEEL

10.1 M ATERIALS

In addition to design requirements specified in the Structural Steel Fabrication Specifica-tion, DGS-CU-020, and Structural Steel Erection Specification, DGS-CU-021, the designof all steel shall comply with the AISC Manual of Steel Construction using the followingmaterials:

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Structural Steel ASTM A36/A 36M

Handrail ASTM A 36/A 36M

Unfinished Bolts ASTM A307

High Strength Bolts ASTM A 325M

Unfinished Nuts ASTM A 563M, Grade DH

Hardened Steel Washers ASTM F436

Structural Pipe ASTM A 53/A 53M Type E or S, Grade B

Structural Tubing ASTM A500 Grade B

Euronorm (EN) or British Standard equivalents may be used in lieu of the above.

Structural plates and shapes dimensions and fabrication tolerances shall comply with Eu-ronorm (EN) standards. Different standards shall require COMPANY approval.

Material norm once selected and approved at PROJECT onset shall be maintainedthroughout for all structural items. Equivalent, mixed or unknown norms shall not be al-lowed subsequently. Material suppliers shall be exclusively from COMPANY approvedsupplier list.

10.2 GENERAL

10.21 Shop connections shall be welded, unless noted otherwise. Welding electrodes with a

minimum tensile strength of 485 N/mm2 shall be used

10.2.2 Field bolted connections shall use high strength bolts using bearing-type connections.Bolts shall be designed with threads included in the shear planes. Secondary or lightlyloaded members, such as girts, purlins, stairs, ladders, handrails, etc., may use 16mm(5/8") diameter unfinished bolts

10.2.3 All connections which are not detailed or otherwise noted on the design drawings shall beshop bolted/welded and field bolted Framed Beam Connections as shown in AISC Manualof Steel Construction (ASD). Use the maximum number (n) rows of field bolts compatiblewith the beam T dimension for each beam depth under consideration. Use a minimum of6mm shop weld "A" as shown in the Manual. Verify that connections will allow use ofpower tools to install the bolts

10.2.4 All critical joint forces shall be indicated on Engineering Drawings for connection designwhere this task is delegated to the Erector/Fabricator. Individual Load Case forces shall beshown on “stick” diagrams with a right handed sign convention and the most stringentLoad Combination(s) to be considered in the design shall be clearly marked with appropri-ate Load Case factors. Connection design shall be reviewed and approved by the CON-TRACTOR

10.2.5 Gusset plates shall not be thinner than the connecting part of the member or less than10mm thick

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10.2.6 Steel structures base plates except for standard pipe supports, shall be at least equal in

thickness to the column cross section largest thickness but not less than 16mm10.2.7 As a minimum, platforms and walkways shall be covered with 35mm by 5mm serrated

grating or 6mm thick checkered plate. The weight of removable flooring sections shall notexceed 70kg

10.2.8 Structural tees shall be used in lieu of back-to-back double angles or channels for bracingmembers not fully enclosed within a building. Double angles may be used only in starshape cross sections. Double channels may be used only in box sections.

10.2.9 Platforms and walkways shall be designed for a maximum deflection of 6mm for5.0 KN/m2 load or to the material allowable stresses

10.2.10 All handrails shall conform to ASTM A 36/A 36M

10.2.11 Welding shall conform to the AWS D1.1/D1.1M. All welding electrodes shall meet filler

metal requirements given in AWS D1.1/D1.1M. The electrode material shall be E70XX. Allwelds shall be continuous.

10.2.12 Grating shall conform to ASTM A 1011/A 1011M or BS 4592. The grating size and methodof attachment shall be indicated in the project specifications. Grating and fixing material(clips) shall be hot-dip galvanized in accordance with ASTM A 123/A 123M and A 143/A143M

10.2.13 Checkered floor plate shall be four-way, raised pattern steel plate in accordance with ASTM A 786/A 786MM with a minimum thickness of 6mm, exclusive of the raised patternheight. Plate material shall conform to ASTM A 36/A 36M. Checkered Floor Plate mayonly be used with COMPANY prior specific approval.

10.2.14 The following bolts shall be used for all connections unless higher strength bolts are re-

quired and are noted on the drawings: Bolts 20mm and larger shall be high strength ASTM A 325M or A 490M; Bolts 16mm and smaller shall be in accordance with ASTM A 307

Unless noted otherwise on the drawing, minimum bolt size shall be as follows:

For main members: minimum 2 no. 20mm spaced not more than 6 bolt diametersand not farther than 6 bolt diameters from stem root

For railings and ladders: 16mm (refer to applicable STANDARDS)

For ladder cages: 12mm (refer to applicable STANDARDS)

For stair treads: 10mm (refer to applicable STANDARDS)

10.2.15 A minimum of two 20mm anchor bolts shall be used for steel structures main memberbase plates. 16mm anchor bolts may be used on base plates of secondary members such

as stair stringers, ladders, light access platforms, lightly loaded miscellaneous pipe sup-ports with an operating load not exceeding 5.0kN and height not exceeding 2.0m abovebase.

Anchor bolts sizes based on design requirements shall include a 3mm corrosion al-lowance. Anchor bolt projections shall not protrude more than one bolt diameter abovetop of nut.

10.2.16 All embedded items shall be ASTM A 36/A 36M material and shall be hot-dip galvanized.CONTRACTOR shall develop a detail, which effectively seals the junction of embeddeditems and concrete, for COMPANY approval.

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11.0 CONCRETE

11.1 M ATERIAL

In addition to the requirements of this specification, the design of concrete foundations andstructures shall also be in accordance with the Concrete Design Specification, DGS-CU-013, and the Concrete Construction, Formwork and Coatings Specification, DGS-CU-010.

11.1.1 Reinforcing Steel: Reinforcing steel shall conform to BS 4449 Grade 460. Epoxy coatingsshall not be used.

Welded wire fabric shall conform to BS 4483 or ASTM A 185/A 185M. Epoxy coatingsshall not be used.

Where reinforcing is required to be electrically continuous for any future cathodic protec-tion of concrete structures, this shall be stated on the Project drawings.

11.1.2 Anchor Bolts: Anchor bolts shall conform to ASTM A 36/A 36M. Nuts shall be ASTM563M Class 5 and dimensional style suitable for the bolt size as per COMPANY standarddwg STD-CU-D-109

In special cases where A 36/A 36M anchor bolts are not sufficient, ASTM A 572/A 572Mshall be used. All anchor bolts and nuts shall be hot dip galvanized

11.1.3 Grouting: All grout materials and application procedures shall be used in accordance withDGS-CU-011 including relevant addendum.

12.0 MASONRY

12.1 M ATERIALS

All work shall comply with the requirements of DGS-AU-052 using the following materials:

Mortar to ASTM C 2701

Type S, f c = 12.4 N/mm2 or Type M, f c = 17.2

N/mm2

Hollow-Unit Concrete Block to ASTM C 90

Average of 3 Units Compressive Strength = 13.1

N/mm2

Concrete Building Brick to ASTM C55

Average of 3 Units Compressive Strength = 17.2

N/mm2

Hollow Masonry Units MasonryPrism Specified Strength to ASTM C1314

f m = 10.2 N/mm2

Concrete Building Bricks MasonryPrism Specified Strength to ASTM C1314

f m = 16.3 N/mm2

Reinforcing Steel BS 4449 with minimum yield strength of460 N/mm2.

(1) Type to be selected as per ASTM C 270 recommendations

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13.0 FIREPROOFING

Fireproofing shall be in accordance with the Concrete Construction, Formwork and Coat-ings Specification, DGS-CU-010, and the Fireproofing Requirements Specification, DGS-CU-012. Type and extent shall be shown on the drawings.

14.0 FOUNDATIONS

14.1 Detailed design of foundations for all equipment and structures shall be designed in ac-cordance with recommendations outlined in the Project Soils Report.

14.2 Specific foundation design provisions under blast loading shall be as stipulated under sec-tion 7.15 above.

15.0 ALLOWABLE STRESSES

Allowable stresses and permissible limit states in the applicable codes specified above for

structural steel, concrete, and masonry shall apply for all designs.Increase in allowable stresses or limit states for all structural elements and their connec-tions shall be considered only when so permitted by the applicable design code. Such in-crease shall be reflected by introducing code-reduced load factors to the load combina-tion.

In Test load combinations without wind loading, a 20% allowable stress increase shall bepermitted in steel structural elements and in foundation bearing pressures.

16.0 STABILITY CHECKS

Stability checks shall be performed for all structures including overall sliding of buildingssubject to blast or earthquake loads and allowable lateral displacement checks of piledfoundations.

The stability of the structure shall be checked for the non-factored load combinations.

The minimum safety factors for wind against overturning and sliding shall be 1.5. Theminimum safety factor for earthquake against overturning and sliding shall be 1.25. For allother load combinations, stability ratio shall be 2.0. Note that Ft may be taken as zerowhen calculating soil bearing stresses. Unless given in the Project Soils Report, friction

coefficient between soil and concrete foundation may be taken as tan ( = angle of inter-nal friction of the soil in degrees).

An uplift (buoyancy) check shall be performed on any structure that may be within the wa-ter table in the empty condition. The minimum safety factor against uplift shall be 1.1.

In determining safety factors, allowances shall be made for future removal of weights suchas removal of soil.

Foundations for vertical vessel on stacks shall meet the following stability criteria againstoverturning.

a. At least 80% of the foundation shall be in compression for the design overturningmoment during empty or, erection condition.

b. At least 90% of the foundation shall be in compression for the design overturningmoment during normal operating condition with the exception of (c) below.

c. Foundations for tall vertical vessels (h/d>10), shall be in full compression (100%) forthe design overturning moment during normal operating condition.

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T k DGS CU 002 R 2 M 2009 (Wi h Add h ) I iti l P 27 f 27

Foundation piling shall be considered where soil structural behavior can be affected by

liquefaction from excessive vibrations such as those generating from high frequency vi-brating equipment in high water table zones.

FIGURE 1

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