4.15.MP75 CVL 015 Strl Des Criteria

7/24/2019 4.15.MP75 CVL 015 Strl Des Criteria

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450-550MW Combined Cycle Power Plantand 8 MIGD SWRO Plant

STRUCTURAL DESIGN CRITERIA

MP75/CVL/015 Rev. 0 Page 1of27

450-550MW COMBINED CYCLE POWER

PLANT AND 8 MIGD SWRO PLANT

MP75/CVL/015

TECHNICAL SPECIFICATION


TABLE OF CONTENTS


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1.0 INTRODUCTION ......................................................................................................... 4

2.0 CODES, STANDARDS AND REGULATIONS ............................................................. 4

2.1 Codes and Standards .................................................................................................. 42.2 Documents and Specifications ..................................................................................... 52.3 References .................................................................................................................. 62.4 Regulatory Requirements and Authorities .................................................................... 6

3.0 SITE CONDITIONS ..................................................................................................... 6

4.0 DESIGN RESPONSIBILITIES ..................................................................................... 7

4.1 General ....................................................................................................................... 74.2 Pre-Assembly .............................................................................................................. 74.3 Calculations ................................................................................................................. 7

5.0 DESIGN DATA ............................................................................................................ 8

6.0 DESIGN LOADS ......................................................................................................... 8

6.1 General ....................................................................................................................... 86.2 Dead Loads ................................................................................................................. 96.3 Live Loads ................................................................................................................... 9

6.3.1. Facilities and Buildings ................................................................................................ 96.3.2. Retaining Walls.......................................................................................................... 106.3.3. Slabs on Ground and Trafficable Culverts .................................................................. 10

6.4 Equipment loads ........................................................................................................ 106.4.1. General ..................................................................................................................... 106.4.2. Impact and Dynamic Loads........................................................................................ 116.4.3. Vibration Loads.......................................................................................................... 11

6.5 Wind Loads ............................................................................................................... 126.6 Earthquake Loads...................................................................................................... 126.7 Temperature Effects .................................................................................................. 12

6.8 Combined Loads ....................................................................................................... 136.8.1. Loading Combinations ............................................................................................... 136.8.2. Construction Loads .................................................................................................... 136.8.3. Lifting Loads .............................................................................................................. 13

7.0 SERVICEABILITY ..................................................................................................... 13

7.1 Acceptable Deflections .............................................................................................. 137.2 Slenderness Ratios for Steelwork .............................................................................. 15

8.0 DESIGN OF INDIVIDUAL ELEMENTS ...................................................................... 15

8.1 Earthworks ................................................................................................................ 158.2 Foundations............................................................................................................... 15

8.2.1. General ..................................................................................................................... 158.2.2. Footings .................................................................................................................... 15

8.2.3. Holding Down Bolts ................................................................................................... 168.2.4. Shear Keys ................................................................................................................ 168.2.5. Piers / Piles ............................................................................................................... 168.2.6. Raft Slabs .................................................................................................................. 168.2.7. Machine foundations .................................................................................................. 178.2.8. Tank Bases ............................................................................................................... 17

8.3 Concrete Structures ................................................................................................... 178.3.1. General ..................................................................................................................... 178.3.2. Materials.................................................................................................................... 188.3.3. Concrete cover for reinforcement ............................................................................... 188.3.4. Slabs on Grade.......................................................................................................... 198.3.5. Earth Retaining Structures ......................................................................................... 19


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8.3.6. Bases to Pumps and Rotating Equipment .................................................................. 198.3.7. Liquid Retaining Structures ........................................................................................ 20

8.3.8. Suspended Floor Slabs .............................................................................................. 208.3.9. Crack Control ............................................................................................................ 208.3.10. One-Way Shear ......................................................................................................... 20

8.4 Steelwork .................................................................................................................. 208.4.1. General ..................................................................................................................... 208.4.2. Materials and Preferred Steel Sections ...................................................................... 218.4.3. Bolting ....................................................................................................................... 218.4.4. Welding ..................................................................................................................... 218.4.5. Bracing ...................................................................................................................... 218.4.6. Corrosion Protection .................................................................................................. 228.4.7. Flooring ..................................................................................................................... 228.4.8. Stairs, Walkways and Landings ................................................................................. 228.4.9. Handrails and Kick-Plates .......................................................................................... 238.4.10. Ladders ..................................................................................................................... 23

8.4.11. Crane Runway Beams and Monorails ........................................................................ 238.4.12. Grouting of Baseplates .............................................................................................. 248.4.13. Purlins and Girts ........................................................................................................ 25

8.5 Cladding .................................................................................................................... 258.6 Concrete Masonry ..................................................................................................... 25

9.0 DESIGN OF FACILITIES ........................................................................................... 25

9.1 Tanks and Vessels .................................................................................................... 259.2 Pipe Racks ................................................................................................................ 25

9.2.1. Vertical Loads ............................................................................................................ 269.2.2. Transverse Loads ...................................................................................................... 269.2.3. Longitudinal Loads..................................................................................................... 269.2.4. Longitudinal Beams ................................................................................................... 279.2.5. Intermediate beams at tier levels................................................................................ 27

9.2.6. Transverse restraint guides........................................................................................ 279.2.7. Cable Trays ............................................................................................................... 27


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1.0 INTRODUCTION

This design criteria defines the general and technical requirements for the structural designof buildings, structures and foundations for the Project No. D15002 (450-550 MWCombined Cycle Power Plant and 8 MIGD SWRO Plant at the DUBAL Jebel Ali Site, Dubai,UAE).

All design shall be in accordance with this Design Criteria, the Specifications and theStandards and References set out in Section 2 and shall comply with the owners SafetyGuidelines. Alternative documents shall only be adopted with the owners approval.

2.0 CODES, STANDARDS AND REGULATIONS

All design, work performed and materials furnished under this design criteria shall complywith the latest issues (unless otherwise specified), addenda and supplements of all relevant

standards, regulations, codes and statutory requirements in the United Arab Emirates.In the event of inconsistencies between standards, the more stringent requirements shallbe applied.

The following are the principal standards, codes, guidelines and references that shall beused for the structural design.

Refer to Chapter 35 of the IBC (2009) for a list of all Standards referenced throughout theIBC.

2.1 Codes and Standards

ASCE 7-05 Minimum Design Loads for Buildings and OtherStructures

ASCE 37-02 Design Loads on Structures During Construction

AISC 360-05 Specification for Structural Steel Buildings

AISC 341-05 Seismic Provisions for Structural Steel Buildings

AISC Design Guide 27 2005 Structural Stainless Steel

ACI 318M-08 Building Code Requirements for Structural Concreteand Commentary

ACI 530-08 Building Code Requirements for Masonry Structures

ANSI/AWC NDS 2012 National Design Specification for Wood Construction

AA ADM 2010 Aluminium Design Manual 2010, Aluminium Association

AISI S100-07 North American Specification for the Design of Cold-Formed Steel Structural Members, American Iron andSteel Institute

BS4449:2005 Steel for the reinforcement of concrete. Weldablereinforcing steel. Bar, coil and decoiled product


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BS 5395-1:2010 Stairs - Part 1: Code of practice for the design of stairswith straight flights and winders

BS EN 1990:2002 Eurocode: Basis of structural design

EN 1991-1-4:2005 Eurocode 1: Actions on structures Part 1-4: Generalactions Wind actions

EN 1991-3:2006 Eurocode 1: Actions on structures Part 3: Actionsinduced by cranes and machinery

EN 1992-1-1:2004 Eurocode 2: Design of Concrete Structures Part 1-1:General rules and rules for buildings

EN 1992-3:2006 Eurocode 2: Design of Concrete Structures Part 3:Liquid retaining and containment structures

EN 1993-6:2007 Eurocode 3: Design of Steel Structures Part 6: Cranesupporting structures

EN 197-1:2011 Cement. Composition, specifications and conformitycriteria for common cements

EN 10080:2005 Steel for the reinforcement of concrete. Weldablereinforcing steel. General

Refer to the technical specifications below for a list of relevant materials standards.

Alternative design codes may only be used with approval from the Company.

Any conflicts between approved codes shall be brought to the engineers attention forresolution.

2.2 Documents and Specifications

The following documents shall also be complied with: -

MP75/CVL/020 Design Criteria - Civil

MP75/CVL/021 Specification Insulated Aluminium Cladding

MP75/CVL/022 Specification Non insulated cladding

MP75/CVL/001 Specification - Building Works

Volume 2A, Section 10 Specification - Site Data

MP75/CVL/018 Specification - Earthwork, Trenching and Backfill

MP75/CVL/006 Specification - Earthwork, Structural Excavation andBackfill

MP75/CVL/004 Specification - Concrete Supply

MP75/CVL/005 Specification - Concrete Works

MP75/CVL/012 Specification - Supply, Installation & Testing of Piling


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MP75/CVL/013 Specification - Precast Concrete Elements

MP75/CVL/003 Specification - Concrete Block Masonry

MP75/MEC/011 Specification - Painting and Galvanizing

MP75/CVL/016 Specification - Structural Steelwork Supply andFabrication

MP75/CVL/017 Specification - Structural Steelwork Erection Work

Volume 2A, Section 9 Civil Specification

2.3 References

AISC Steel Construction Manual, 13thEdition (or later)

AWS D1.1/D1.1M:2004 Structural Welding Code Steel

AWS D1.8/D1.8M:2009 Structural Welding Code Seismic Supplement

API 650-2008 Welded Tanks for Oil Storage

Guide to Industrial Floors and Pavements by Cement Concrete and AggregatesAustralia

Guide to the Construction of Reinforced Concrete in the Arabian Peninsula,CIRIA Publication C577

ACI 351.3R-04 Foundations for Dynamic Equipment

CP2012-1:1974 Foundations for Machinery

Design of Structures and Foundations for Vibrating Machines by Arya, ONeill andPincus

2.4 Regulatory Requirements and Authorit ies

All design, materials, workmanship and practises shall be in accordance with the localagencies that have jurisdiction over the project.

Relevant regulatory requirements on the project includes but not limited to the followings:

International Building Code (IBC), 2009

Seismic design Code for Dubai by Dubai Municipality

All relevant UAE Workplace Health and Safety Acts

All relevant UAE Hazardous Substances Regulations All relevant UAE Environmental Protection Acts

UAE Fire and Life Safety Code of Practice, 2011

UAE Civil Aviation Regulations

3.0 SITE CONDITIONS

General site information and climatic data are included in Volume 2A, Section 10 SiteData.


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4.0 DESIGN RESPONSIBILITIES

4.1 GeneralThe Contractor organizations design & lead engineers shall become familiar with thefunctions and operating conditions of the plant such as the movement of materials andliquids, rotating masses, out of balance forces, temperature changes, impact forces,spillage loads, and build up of scale.

The design engineer shall ascertain, in conjunction with the lead engineer and inconsultation with the process, mechanical, and electrical engineers, the loads created byplant, equipment, operational conditions, and stacked materials during construction foreach facility.

All design input shall be authorised by the lead engineer prior to application.

Structures supporting plant and equipment should be designed with consideration for the

proposed function and the economical fabrication and erection of the structures.Constructability and access for maintenance shall be considered. The bracing at groundlevel should be kept to a minimum so that easy access is provided for maintenance andoperations.

All calculations and drawings shall be documented in SI units and the English language.

4.2 Pre-Assembly

Prefabricated, shop welded and pre-assembled steelwork is an option as opposed to fieldbolted steelwork. Similarly, precast concrete is an option as opposed to in-situ reinforcedconcrete. The design engineer shall co-ordinate with the lead engineer in determiningwhere prefabrication and pre-casting is to be adopted.

The sequence of construction, installation of mechanical equipment and road transport and

lifting limitations shall be considered in the design process and these should be agreed withthe Pre-Assembly and Construction teams prior to a final design being completed.

4.3 Calculations

All design calculations shall be completed on A4 size project calculation sheets inaccordance with project procedures. All other design data shall be on A4 sized sheets,reducing A3s etc. as necessary.

The basis and assumptions for the design together with all basic data and designinformation and sources of unusual formulae shall be recorded with the calculations. Thecalculations shall include a general arrangement of the facility and any sketches prepared.Calculations together with the data and sketches shall be consecutively numbered, given atitle incorporating the specific facility number for the area, signed, dated and provided with a

project standard cover sheet. The cover sheet shall incorporate the title of the facility andcontain a brief index to the calculations. Each set of calculations shall be logged in to amaster index kept by the lead engineer so that it can be presented to any authority or itsdelegate for approval.

All calculations and drawings shall be independently checked.

The following minimum requirements shall be satisfied.

Project calculation cover sheet, fully lled in and signed accordingly.

Index to show major sections and page numbers.


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A detailed introduction explaining the circumstances and basis for design andthe path chosen.

A summary of the design output.

Sketches that tie in calculations and member location.

Copies of all inputs such as general arrangements, vendor data, geotech info,

data sheets, faxes , emails etc. Wherever possible these should be scanned

or copied as part of the calculations and not just referenced.

Ensure all electronic calculations and any other engineering package output is self

explanatory and easily followed without needing the software for interpretation.

All structural analysis software calculations to include the following:

1. Graphics hard copy frames, sections and each load case.2. Graphics hard copy of governing frame deflection.

3. Graphics hard copy of critical M, V, N diagrams where ever practical.

4. Graphics hard copy of primary load cases in particular wind, wherever practical.

5. Copy of all load case and combination titles.

6. Copy of all load case combinations.

7. Copy of all footing reactions for all load cases.

8. List all structural analysis software les and description.

Add an appendix for hard copy attachments, make the calculation a stand-alone

document where ever possible by attaching thenal IFC drawings to thecalculations.

Ensure there is a HOLDS list; all HOLDS should be cleared prior to nal check andapproval.

Ensure each page is numbered and contains the calculation number.

5.0 DESIGN DATA

For general design data related to temperature, humidity, rainfall and tide heights, refer toSpecification Site Conditions.

Buildings and other structures are generally occupancy category II in accordance with theIBC Table 1604.5. Facilities shall be occupancy category IV where listed as an essential

facility in Table 1604.5.

6.0 DESIGN LOADS

6.1 General

The loads used in the design shall be in accordance with the loads given in this criteria, thespecific loadings as established for each item of equipment, and ASCE 7-05 MinimumDesign Loads for Buildings and Other Structures. The minimum or maximum dead loadsshall be combined in conjunction with other loads, so as to produce the most severecombinations of load imposed on the structure.


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The layout and design criteria for all equipment supported on the structure shall beobtained in writing from the mechanical engineer before design commences.

The design engineer, in consultation with the lead engineer, shall determine the loadsimposed by electrical cables and services pipes.

6.2 Dead Loads

Dead loads shall be determined using ASCE 7-05.

Dead load shall be considered in two categories:

Dead loads unable to be removed from the structures.

Superimposed dead loads

Superimposed dead loads shall be considered as the weight of all materials forming loadson the structure that are not structural elements and which are likely to vary or be removed

during operation or construction of the structure.Superimposed loads may include:

Operating material loads

Piping contents.

A variable portion of electrical cabling load

Lining to tanks / vessels / launders that may be permanently removed

Scale formation to tanks / vessels / launders / pipework

The design engineer shall assess the possibility of the removal of these dead loads, whichwill result in the most severe combination of stresses in the structure.

6.3 Live Loads

6.3.1. Facilities and Build ings

Except where specific equipment loads produce more severe loads, minimum floor verticallive loads shall be as the following table:

Area Uni formlyDistributed Load

(kPa)

Concentrated Load

(kN)

Offices (excl. file rooms, etc.) 3.0 2.7

General plant area elevated

floors

5.0 4.5

Walkway, stairs and landings inbuildings

4.8(100 psf)

4.5

Walkway, stairs and platforms inaccess structures

2.5 2.0

Conveyor gallery walkway,individual walkway span

2.5 2.0


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Area Uni formlyDistributed Load

(kPa)

Concentrated Load

(kN)

Conveyor gallery walkway fortruss design

1.2 kN/m

Control room floors 10.0

Motor rooms, fan rooms 5.0 4.5

Letdown areas and truck aisles 10.0 To be determined for specificlocation

Roof live load 0.6 to 1.0

IBC1607.11.2.1

4.5

These loads are to be verified for the specific area and facility. The structural members areto be designed for the load pattern (either uniformly distributed or concentrated), which hasthe most adverse effect on the supporting member. Generally the concentrated loads in theabove table will be applied to short members that support only a small area of floor.

Stair treads shall be designed for a concentrated vertical load of 1.34 kN (300 lb) inaccordance with the IBC.

Handrails shall be designed for a load of 0.36 kN/m (25 lb/ft) applied in any direction to thetop rail and also 0.89 kN (200 lb) concentrated load applied in any direction (not applied atthe same time).

6.3.2. Retaining Walls

All retaining walls shall be designed for the actual surcharges applied.

Surcharge loads shall not be less than the following:

Minimum vertical surcharge 10 kPa

Normal road traffic 22 kPa (where the distance from the face of the wallto the edge of a road is within half the height of thewall)

Abnormal axle loads: Specific analysis of load distribution

6.3.3. Slabs on Ground and Trafficable Culverts

Vehicle loads from highway registered vehicles shall be as per Design Criteria Civil.

For areas not to be trafficable by highway registered vehicles, and areas to be trafficable bynon-highway registered vehicles, the design axle loads or other point loads shall bedecided appropriately by the design/lead engineer.

6.4 Equipment loads

6.4.1. General

Layout and design criteria for the support of equipment items, together with Certified Sellerdrawings, shall be provided by the relevant discipline engineer. Equipment reactions shall


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be supplied by the Seller and shall indicate all possible loading combinations, dynamiceffects and allowable deflections of supporting structures.

6.4.2. Impact and Dynamic Loads

The static load of equipment shall be multiplied by the following factors to allow for impact:

Reciprocating machinery, crushers and pumps 3.0*

Rotating machinery 2.0*

Mobile equipment 1.2

Fork lifts 1.6

Hangers supporting floors and balconies 1.35

Carry and return idlers at loading points 2.0

Carry and return idlers elsewhere 1.1* These values shall be used for preliminary design only. Actual certified dynamic loadvalues nominated by the equipment Seller shall be used in the final design.

6.4.3. Vibration Loads

Certified Seller drawings giving design parameters and operating frequencies shall beobtained from the manufacturer for each piece of equipment. The dynamic effect on theimmediate supports and on the main structure shall be evaluated using un-factored actualmasses.

Areas subject to dynamic loading shall be checked for dynamic response against limits forworkers by ISO 2631-1:1997, Mechanical vibration and shock- Evaluation of humanexposure to whole-body vibration.

Wherever possible, vibrating equipment shall be isolated from the main structural framing.However, where such equipment is supported on structural members, the following tableprovides a guideline for the desired relationship between the frequency of the vibratingloads and the frequency of the supporting members:

Length of Beam Type of Supports Rat io o f Support and EquipmentFrequencies

5m or less Directly connected tocolumn

1.5

Greater than 5m Directly connected tocolumn

2.0

5m or less Not directly connectedto column

1.5

Greater than 5m Not directly connectedto column

2.0

The natural frequency of bracing adjacent to the equipment shall also be checked. Thedesired relationship between the natural frequency fnand the forcing frequency ff of thebrace shall be as follows: fn/ffis less than 0.75 or greater than 1.5.


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The design engineer shall consider the effects of fatigue in the design of supportingmembers and their connections. Fatigue shall be checked in accordance with EN 1993 and

shall be based on the relevant number of cycles applicable to the beam or to the detailbeing designed and shall take into account the fabrication details of the beam and itscomponents.

6.5 Wind Loads

The basic wind speed for the site is 45 m/sec. The basic wind speed is the 3-second gustspeed at 10 m height in exposure category C with a 50 year return period.

The site exposure category for all wind directions shall be taken as exposure D. The designwind speed is to be adjusted for the site exposure category and the building height aboveground in accordance with the procedures in ASCE 7-05.

The importance factor by ASCE 7-05 Table 6.1 shall be 1.0 for occupancy category IIfacilities and 1.15 to occupancy category IV facilities.

The topographic factor and wind directionality factor in ASCE 7-05 shall be taken as 1.0.

Wind forces shall be determined in accordance with ASCE 7-05. Drag coefficients may alsobe determined in accordance with EN 1991-1-4.

The operating wind speed VOshall be taken as 20 m/sec. This is the wind speed applicableduring shutdown of the plant and also during erection procedures.

The serviceability wind speed VS for serviceability deflection checks shall be based on a10 year return period. It shall be taken as 0.9 x 45 = 40.5 m/sec.

6.6 Earthquake Loads

Seismic Loads - Structures and foundations shall be designed to withstand a seismic load

in accordance with the seismic provisions of the IBC 2009 standard and relevant clauses ofthe ASCE 7 standard, based on the parameters as obtained from Seismic design Code forDubai by Dubai Municipality.

6.7 Temperature Effects

Structures shall be designed to accommodate movements due to environmental andoperational thermal expansion and contraction. Any operational temperature effects onstructures shall be assessed. The designer shall provide installation temperaturepositioning tolerances for bearings and expansion joints. Bearings shall be designed for aminimum installation tolerance of +/- 25mm in addition to the thermal movementallowances.

Concrete shall be detailed with expansion joints as required to accommodate thermalexpansion.

Design steelwork installation temperature shall be between 25oC and 45oC. The steeltemperatures used to calculate contraction or expansion movements from an installationposition shall be:

Locations exposed todirect sunlight

Other Locations

Max. temperature (oC) 65 50

Min. temperature (oC) 5 5


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6.8 Combined Loads

6.8.1. Loading Combinations

Loading combinations and factors shall be generally as defined in BS EN 1990 and BS EN1991, BS EN 1992, or BS EN 1993 whichever applicable. In addition, loading combinationincluding seismic loads shall be generally as defined in IBC.

Live load shall include loading by cranes.

The imposed load shall include for dynamic effects where appropriate. The imposed andwind loads shall be combined with the dead load and with each other in such a way as togive the worst possible stresses at any location. In addition thermal effects shall beconsidered where significant, acting in conjunction with the combined load cases.

Load cases need not be combined arbitrarily without regard for practical possibilities e.g. anoutdoor crane need not be capable of carrying its maximum operating load and maximum

wind load simultaneously, since it would not be operating whilst subject to the maximumwind loading.

6.8.2. Construction Loads

Consideration shall be given to the construction sequence in order to ensure that astructure is able to carry the design loads which act before completion of the structure and,also, that exceptional loads resulting from the construction sequence are catered for. Thisconsideration shall include dead, wind and thermal loads together with suitable imposedloads, as appropriate. 2.5 kPa DL construction load for platforms shall be used, andoperating wind load shall be used because of the temporary nature of the loads.

6.8.3. Lifting Loads

Consideration shall be given to the loads induced during lifting and placement.

7.0 SERVICEABILITY

7.1 Acceptable Deflect ions

The following table shall be used as a guide to determine acceptable deflections. Unlessnoted otherwise, deflection is for the serviceability limit state load combination.

Element Acceptable Deflection for Serviceability

Limit States

Floor beam Span dead + live Span live load only

250 360

Span dead + live, supporting deflection sensitive500 equipment or as required by equipment vendor.

Cantilever Floor Beam Span for cantilever dead + live150

Floor Beam with dynamicloading

Refer ISO 2631-1:1997, Mechanical vibration and shock -Evaluation of human exposure to whole-body vibration


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Element Acceptable Deflection for Serviceability

Limit States

Crane beams / monorails

(per EN 1991-3)

Span for vertical static loads at Mid Span500

Note: For cantilevers witha backspan allow forrotation of the beam atsupports

Lateral deflections to bebased on the top or bottomflange mobilization, as

applicable.

Lesser of 10 mm and Span 600

for lateral dynamic loads at Mid Span

Span for vertical static loads at Cantilever300

Span for lateral dynamic loads at Cantilever

400

Lateral deflection ofsupports at level of cranerail (per EN 1991-3)

Lesser of 10 mm and Hc 500

(Hc = height of crane rail above footing or fully verticallybraced horizontal plane)

Building sway withoutcranes, steel cladding

Height150

Building sway withoutcranes, masonry cladding

Height250

Roof beam Span dead + live250

Purlins and girts Span serviceability wind only150

Conveyor trusses Span Vertical

300

Span Lateral

300

Relative end baydeflection

End bay frame spacing 250

Relative horizontaldeflection between floors

Height between floors 300

Grating / Floor Plate for pedestrian live load: 5mm or Span whichever is the less 180

Pipe Racks Height - subject to pipe stress requirements 300


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7.2 Slenderness Ratios for Steelwork

Item Maximum Slenderness Ratio

Columns supporting vibratingequipment

100

Columns, trestle legs generally 180

Compression bracing subjectto permanent loads or belttensions

180

Compression bracing subject

to transient loads i.e. wind,seismic

250

8.0 DESIGN OF INDIVIDUAL ELEMENTS

8.1 Earthworks

Compaction standards shall be expressed as a percentage of the materials ModifiedProctor maximum dry density (MDD) at its optimum moisture content.

The required degree of compaction shall be as follows:

95% for fill generally.

95% for a minimum depth of 300 mm immediately under concrete slabs andfootings placed on fill or the in-situ subgrade

Embankments composed of engineered fill and cuts in existing site material shall be to aslope of 1 vertical to 2 horizontal unless proven by calculations otherwise.

8.2 Foundations

8.2.1. General

Foundations shall be designed in accordance with the Geotechnical Report for the specificfacility.

Where over excavation has occurred backfill shall be either mass concrete or selectedgraded granular material from an approved source in accordance with SpecificationEarthworks, Structural Excavation and Backfill and shall be compacted in layers of 150mm maximum compacted thickness to the required standard of compaction.

8.2.2. Footings

Foundations shall be designed for the applicable load combinations.

Maximum total settlements, differential settlements and interaction between foundationsand structures shall be considered during design.

In checking uplift stability, only the soil directly above the footing shall be taken into accountunless proved otherwise.


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The effect of groundwater level shall be considered for footing stability.

Footings shall be cast on a 50 mm layer of blinding concrete.The top of footing bases shall be a minimum of 450 mm below the finished grade or450 below the slab on grade low point.

The minimum height from top of concrete to finished grade shall generally be:

Exposed column pedestals 300mm

Plinths for equipment 300mm

The minimum height from top of concrete to paving high point shall generally be:

Exposed column pedestals 150mm

Plinths for equipment 150mm

8.2.3. Holding Down BoltsAll columns with a mass of more than 140 kg shall have a minimum of four holding downbolts per base plate unless erected as part of a stable self-supporting structure.

The capacity of holding down bolts for shear and tension shall be in accordance withACI 318, Appendix D or approved equivalent. The total design shear load shall beconsidered as applied to a maximum of two front bolts (the bolts closest to the potentialconcrete breakout edge). Where a shear key is required, refer Section 8.2.4.

All holding down bolts, nuts and washers shall be hot dip galvanised. Material shall beGrade 36 to ASTM F1554 or Grade S275JR to EN 10025 (or approved equivalent). Boltsshall be painted following installation of nuts and approval of the erected steelwork. Thepaint system shall be in accordance with specification Painting and Protective Coatings.

Small items (such as ladders and stair stringers) may be fixed to concrete using chemicalanchors. These items shall be stainless steel or hot galvanised unless otherwise approved.

Minimum sizes of bolts shall be as follows:

Holding down bolts 20mm dia.

Mechanical or chemical anchors 16mm dia.

8.2.4. Shear Keys

Shear keys shall be used where the applied ultimate shear load to the baseplate exceeds75 kN.

Shear keys shall be single or cruciform plates in preference to an open H section. Theyshall be full penetration butt welded to the baseplate unless otherwise approved.

8.2.5. Piers / Piles

The design parameters for piers shall be in accordance with the Geotechnical Report forthe specific facility.

8.2.6. Raft Slabs

Raft slabs shall be designed in accordance with the Geotechnical Report for the specificfacility.


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8.2.7. Machine foundations

A finite element analysis shall be used to verify that the natural frequency of the foundationis sufficiently removed from the forcing frequency of the equipment. The dynamic responseof the foundation shall be calculated and checked against agreed acceptability criteria.

References for machine foundations include:

ACI 351.3R Foundations for Dynamic Equipment

CP2012 Foundations for Machinery

Design of Structures and Foundations for Vibrating Machines by Arya, ONeill andPincus

8.2.8. Tank Bases

Flat bottomed, ground supported tanks shall generally be supported on an annular ring of

concrete under the tank shell. Where additional uplift resistance is required or increasedaxial bearing capacity is required, an inverted tee shaped ring foundation shall be used. Afull raft slab under the tank shall be used where required for stability.

Tank foundation loads shall be derived from an API 650 analysis of the tank. Working loadsfrom the API 650 analysis shall be factored to derive limit state load combinations forfoundation design.

8.3 Concrete Structures

8.3.1. General

Concrete design shall be in accordance with ACI 318 or BS EN 1992: Euro code 2.

Site soils are generally corrosive. Concrete surfaces below ground shall receive surface

protection as per specification Concrete Works.Concrete surfaces above ground shall receive surface protection where noted inspecification Painting and Protective Coatings.


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8.3.2. Materials

Concrete strength grade designations as per EN 1992 and corresponding usage, shall beas follows:

Appl ication StrengthGrade

Designation

MaximumAggregate

Size

CharacteristicCompressive Strength

fckat 28 days MPa

All concrete U.N.O C40/50 20 40

Foundations: Concrete in contactwith the soil

C40/50 20 40

Piles C40/50 20 40

Silo walls C40/50 20 40

Blinding C12/15 20 12

Marine facilities C50/60 20 50

Miscellaneous Concretee.g. Drainage Structures, RoadSignage and Fencing Footings

C25/30 20 25

Sprayed Concrete Applications C40/50 10 40

Grout for Masonry Block Fill C20/25 10 20

Exposure classification for exposed Concrete Structures shall be in accordance withEN 1992-1-1.

Cement Type: Ordinary Portland cement to EN 197-1, incorporating fly ash, silica fume orblast furnace slag where specified.

Reinforcing steel shall be as Grade B500C (yield strength 500 MPa minimum) bars toEN 10080 / BS 4449.

8.3.3. Concrete cover for reinforcement

Minimum concrete protective cover (mm) for reinforcement shall be as follows:

(A) Foundations and pedestals in contact with the ground

With membrane or blinding concrete 75 Without membrane 75

Tops of footings 75

Formed 75

Bored piers 100

Precast footings 50

Precast piles 50

(B) Other surfaces in exterior environments


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Formed 50

Top and bottom surfaces of slabs 50(C) Sealed interior environments 40

8.3.4. Slabs on Grade

Slab design, including joint selection and spacing, shall be guided by reference Guide toIndustrial Floors and Pavements by Cement Concrete and Aggregates Australia orequivalent. Joint detailing is to be approved by the lead engineer. The design engineer shalltake account of any loading, both during construction and plant operations, from mobileequipment, cranes and scaffolding.

As a minimum, provide a 150mm thick slab reinforced with A252 (8 mm bars at 200 mmcentres) throughout to top face.

8.3.5. Earth Retaining Structu resRefer to geotechnical reports for more accurate information on backfill material to earthretaining structures.

For flexible structures such as retaining walls, the lateral earth pressure coefficient shall betaken as the active condition.

For more rigid construction the at-rest pressure shall be used. Retaining structures subjectto repeated traffic loading, shall take into account the effect of long term compaction thatmay lead to a pressure approaching the at-rest pressure.

Passive pressures shall not be assumed to resist lateral forces unless substantialmovement of the structure can be accommodated.

The upper 300 mm of soil below finished grade shall be ignored when considering the

contribution of passive resistance to resist lateral forces.

Free standing cantilever retaining walls shall have a factor of safety against overturning andsliding of at least 1.5.

8.3.6. Bases to Pumps and Rotating Equipment

Individual bases shall be sized to weigh 3 times the weight of pumps and small equipment.This ratio can be reduced to 2 where the base is integral with a slab on grade.

A dynamic analysis of machine foundations shall be performed where directed by the leadengineer. This analysis would typically be a hand method of analysis and would typicallyapply to machines that are out of balance by design.

For large rotating equipment the lead engineer may direct that the design is performed

using a nite element analysis.

Dynamic deections and velocities shall be no greater than the vendor requirements andapproved by the lead engineer.

As a guide, to avoid resonant response problems, the operating frequency should be lessthan 0.7 times the base natural frequency or more than 1.4 times the base naturalfrequency.

Refer to Section Error! Reference source not found.for design references.


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8.3.7. Liqu id Retaining Structures

All liquid retaining/storage structures shall be designed assuming maximum height ofcontainment.

All liquid retaining/storage reinforced concrete structures shall be designed in accordancewith EN 19923 or approved equivalent. Refer EN 1992-3, Section 8.3.9 regarding crackcontrol.

Reinforcement shall be provided to each face of the walls and base slabs of liquid/storagetank structures.

8.3.8. Suspended Floor Slabs

Steel decking formwork where nominated on the drawings shall be 1.0 mm thick Condek,or approved equivalent, painted on both sides in accordance with Specification Paintingand Protective Coatings. The paint system shall be as nominated for that particular area of

the Works.The bearing surface of steel supporting the decking formwork and any shear studs incontact with the concrete shall be painted.

Steel decking shall be used as formwork only and not as a permanent structural elementi.e. any composite action shall be ignored in the structural design of the suspended slab.

8.3.9. Crack Control

Minimum reinforcement shall be to EN 1992-1-1, Section 7.3.2. Flexural reinforcement shallalso not be less than ACI 318, Section 10.5.

Control of cracking shall be to EN 1992-1-1, Section 7.3.3 for a crack width of 0.30 mm. Forstructures in seawater and over seawater (as determined by the astronomical high tidecontour), the crack widths shall be calculated and shall not exceed 0.15 mm. The quasi-permanent load to EN 1990 shall be used in determining the crack widths.

For liquid retaining structures, crack control shall be achieved by applying Section 7.3.3 ofEN 1992-3 for a crack width of 0.10 mm.

8.3.10. One-Way Shear

The concrete shear resistance without shear reinforcement shall be calculated inaccordance with EN 1992-1-1 Section 6.2.2. Shear reinforcement shall be calculated inaccordance with Section 6.2.3. The resultant shear reinforcement and detailing shall not beless stringent than ACI 318 Section 11.4.

8.4 Steelwork

8.4.1. GeneralSteelwork design shall be to the limit state design method in accordance with the IBC andAISC 360 and AISC 341 where required or in accordance with BS EN 1993.

Where floor plate is adequately welded to its support beam, it can be considered asrestraining the top flange of the beam. Floor grating fixed by any method shall not beconsidered as restraining the top flange of its supporting beam.

3D welded steel frames shall not be used. 2D welded steel frames are acceptable, subjectto transportation size limits.


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8.4.2. Materials and Preferred Steel Sections

The steel grades and preferred sections that shall be used in design are noted on theSpecification Structural Steel Supply and Fabrication.

8.4.3. Bolting

Unless otherwise shown, structural bolts shall be M20 bolts to ASTM A325M orEN 14399-3 Grade 8.8. Unless noted otherwise, all bolts shall be snug tight. Slip-criticalconnections and tensioned bearing connections shall be designated on the drawings.

All bolts shall be hot dip galvanized. All bolts shall be painted following installation of nutsand approval of installed bolt tensioning. The paint system shall be in accordance withspecification Painting and Protective Coatings.

Bolts in slip-critical connections shall be fully tensioned to exclude slip under serviceabilityloads.

Bolts in tensioned bearing connections shall be fully tensioned but will permit the boltsslipping into bearing mode under serviceability loads.

Fully tensioned ASTM A325 bolts shall be tensioned to AISC 360. Fully tensionedEN 14399-3 bolts shall be tensioned to EN1090-2. Bolts shall be tensioned using the partturn method.

Bolts subject to frequent load reversal from vibrating equipment shall be slip critical. Boltssubject to cyclic or vibrating loads but without load reversal shall be tensioned bearingconnections or slip critical connections.

Capacities of bolts in shear bearing mode shall be based on the assumption that threadsare in the shear plane.

Bolts shall be a minimum size of M20, connected through cleats of 10mm minimum

thickness UNO. For purlins and girts and similar minor connections smaller bolts toASTM 307 (or Grade 4.6 to ISO 4016) and 8mm thick cleats may be used, except wherethe purlin and girt manufacturer recommends high strength bolts and/or thicker cleats.

8.4.4. Welding

Manual welding, semi-automatic and automatic welding shall be in accordance withAWS D1.1 (and AWS D1.8 where required) or in accordance with EN ISO 3834. Electrodesshall have a minimum ultimate tensile strength of 480 MPa and a minimum yield strength of355 MPa.

Welds across the tension flange of members subjected to dynamic loads are not permitted,unless approved by the lead engineer.

The minimum fillet weld size to be used is 6 mm. Where intermittent welds of a greater sizeare specified, the remaining length shall be seal welded using a 3mm fillet weld wherespecified. Butt welds shall be full penetration unless otherwise approved by the leadengineer.

Details that require site welding shall only be acceptable with the lead engineers approval.

8.4.5. Bracing

Vertical bracing shall generally be tube sections. Vertical braces are often long, heavilyloaded members and the fabrication effort required on the end connection is outweighed by


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the structural efficiency of the tube section. Horizontal floor bracing shall generally be anglesections. Open H section bracing is typically not used.

The flexural stiffness of tube bracing end connections shall be considered in determiningthe effective length of compression tube braces.

8.4.6. Corrosion Protection

Corrosion protection is required for all steelwork as per specification Painting andProtective Coatings .

The steelwork shall incorporate the following minimum requirements:

The minimum thickness of rolled sections shall be 6 mm (unless otherwiseapproved).

The minimum thickness of structural hollow sections shall be 4.8 mm and shall besealed unless galvanised.

Arrangements of steel that prevent access for inspection and maintenance shall notbe used, for example back-to-back angle members

Where positioning of members is likely to retain moisture and cannot be avoided,provision of drainage holes is required

Stiffeners on platework exposed to the weather, shall be fully seal welded.

8.4.7. Flooring

The minimum clear head height between top of floor and underside of ceiling beams for allbuildings, structures and conveyor gantries shall be 2200mm.

Unless noted otherwise, floor grating shall be hot dipped galvanised and fabricated from

32mm x 5mm bars at 40mm centres with 6mm square twisted cross bars at 100mmcentres. Load bars shall preferably be at right angles to the direction of predominantpedestrian travel. All edges, ends and penetrations shall be fully banded.

The grating shall be fixed to the support members by hot galvanised bolts and proprietarybent clip fasteners spaced at a maximum of 1000 mm intervals at all supports, but with aminimum of four clips per panel. An alternative fixing system may be used subject toapproval. Where approved, floor grating may be welded to the supporting steelwork.

The standard floor plate thickness is 6 mm.

Floor plate shall have a raised angular pattern and shall be used selectively to preventspillage flowing to lower levels and shall be fully seal welded or sealed by another approvalmethod. Plate shall be welded to support beams or an alternative fixing system may beused subject to approval, however it may not be sufficient to provide lateral restraint.

8.4.8. Stairs, Walkways and Landings

The clear nominal width between handrails for maintenance walkways and stairs (includingspiral stairs surrounding vessels), other than in conveyor gantries, shall be:

900 mm

1200 mm where there is a requirement for a 2 person width, as determined by thelead engineer.

The clear nominal width between handrails for maintenance walkways and stairs inconveyor gantries shall be 750mm.


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Where possible, at the end of stairs, grating shall be aligned such that the load bars areperpendicular to the direction of the stair.

For stairs up to 1200 wide, grating treads shall be fabricated from 32mm x 5mm load barsat 30mm c/c with 6mm square twisted cross bars at 100mm c/c or approved alternative.The stair treads shall be bolted to the stair stringers. Stair treads shall be T6 Webgratetreads or an approved alternative and nosing shall be non-slip, coloured and removable.

The geometry of stair flights and handrails is detailed on the standard drawings and shallconform to the IBC. The loading on stairs and handrails is detailed in Section 6.3 of thisdocument.

8.4.9. Handrails and Kick-Plates

Handrails shall be supplied in prefabricated modules and bolted to the supporting steelworkwherever possible.

8.4.10. Ladders

Rung ladders shall have:

500 mm clear width between stiles unless noted otherwise.

20 mm diameter ladder rungs.

20 mm square ladder rungs turned on edge where advised by the lead engineer.

8.4.11. Crane Runway Beams and Monorails

The loads from cranes and monorail hoists shall be assessed in accordance withEN 1993-3 or approved equivalent. The crane and hoist classification, loads and dynamiceffects, shall be confirmed by the Seller.

The distribution of crane and monorail loads within the crane runway beams and monorailbeams shall be in accordance with EN 1993-6 or approved equivalent. The capacity of thecrane runways and monorail beams for global actions and local effects (e.g. wheel loadeffects) may be to either AISC 360 or EN 1993-6 with their respective loads factors.

Crane rails shall be fixed to the supporting steelwork using Gantrex (or equivalent) clips -not hook bolts. The base of Gantrex clips shall be shop welded to the girders unless notedotherwise.

Splices to crane rails on opposite sides of the crane runway shall be staggered with respectto each other and with respect to the wheelbase of the crane. Rail splices shall not occur atcrane beam splices or over column supports provide a 100mm minimum offset.

Static vertical deflection of cantilever beams shall be evaluated allowing for rotation of thebeam at the support.

Runway beam to column details shall be detailed to allow for vertical and lateraladjustments plus longitudinal displacements of the upper section of the beam caused bybeam deflection.

Supporting columns shall be designed to allow for the maximum eccentricity possible at thebeam to column connection.

Runway beams shall be designed for eccentric loading. Eccentricities to be adopted indesign are to be the maximum of values specified in EN 1993-6 or the following:


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1. Supporting Columns

Total of:(a) Adjustment off centreline available from the design details, and

(b) Column height to beam rail divided by 500 or 25 mm, whichever is less.

2. Runway Beams

Total of:

(a) Rail head divided by 4, and

(b) Beam sweep allowance of beam span divided by 1000 or 3 mm, whichever is greater.

The horizontal actions arising from above eccentricities shall by analysed by the TwinBeam Analogy assumption calculated by deriving horizontal forces acting at the centre ofgravity of the upper and lower beam flanges.

Horizontal loads derived from dynamic actions shall be applied at top of rail level and theresulting horizontal design action on the beam also analysed by the Twin Beam AnalogyMethod outlined above.

To allow for the above vertical and horizontal eccentric effects the following shall beadopted to derive total stresses in the beam top and bottom flanges:

a) Basic Case: Stresses due to vertical and lateral loads with no allowance for verticaland lateral load eccentricity.

b) Vertical Load Eccentricity: Stresses from twin beam analogy.

c) Lateral Load Eccentricity: Stresses from twin beam analogy.

Addition of Cases: a, b, c with stress direction as appropriate to loading direction.

Bending stresses in beam webs resulting from eccentric effects of vertical and lateral loadsshall be evaluated as outlined in EN 1993-6.

Fatigue to runway beams and monorail beams shall be checked in accordance withEN 1993-6 and shall be based on the relevant number of cycles applicable to the beam orto the detail being designed and shall take into account the fabrication details of thestructure and its components.

For welded runway beam sections, fatigue in the welds connecting the upper flange to themember web shall be checked for longitudinal shear stress plus stress arising fromdispersal of the wheel loads through the crane rail depth, upper flange thickness and web.

Curved monorail beams shall be checked with full accountability of the torsion induced.Secondary support steel should be utilised to prevent excessive deflections and torsional

effects.

8.4.12. Grouting of Baseplates

Grout thickness under baseplates shall be a detailed as 50 mm. Grout thickness tounderside of stairs and ladders and other minor steelwork fixed with adhesive anchors shallbe detailed as 20 mm. Grout thickness may be varied where detailed by equipment Sellersor directed by the lead engineer.

Grout type shall be:

General steelwork Masterflow 830 or equivalent, premixed,


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cementitious, non-shrink, free flowing grout

To base plates supporting heavyimpact, vibration and/or rotationalforces

Masterflow 622 or equivalent, heavy duty epoxyresin based grout

8.4.13. Purlins and Girts

Typically purlins and girts shall be cold formed sections.

Purlin supply contractors load capacity tables shall be used to size the purlins and girts forthe calculated loading. Where load capacity tables are not available, capacities shall becalculated in accordance with AISI S100, North American Specification for the Design ofCold-Formed Steel Structural Members, American Iron and Steel Institute.

8.5 Cladding

Cladding shall be in accordance with Cladding Specification.

8.6 Concrete Masonry

Concrete masonry (i.e. blockwork) shall be designed in accordance with ACI 530 BuildingCode Requirements for Masonry Structures.

Infill blockwork shall typically cantilever from the base and shall not incorporate metal ties tothe surrounding structure. Metal ties are not rated for seismic loads nor capable ofsustaining high seismic deflections.

Walls shall be detailed in accordance with the standard drawings.

9.0 DESIGN OF FACILITIES

9.1 Tanks and Vessels

Tanks and vessels containing liquids at atmospheric pressure shall generally be designedin accordance with API 650.

Tanks and vessels shall be designed for the loading produced by the contained material orfluid filled to the top. The design engineer shall check whether the hydro-test load conditionresults in the worst load combination for design of support structures and foundations forvessels and tanks.

When designing supports for tankage and pipe work, the design engineer shall obtaininformation relating to the process fluid (S.G., temperature, etc.) and the likelihood of scaleformation.

In determining the weight of insulation, a density of 200 kg/m3 shall be adopted unlessnoted otherwise. Maximum coefficient of friction to tank bases shall be 0.40 on concrete orasphalt and 0.30 on an HDPE membrane.

9.2 Pipe Racks

In consultation with the piping engineer, the design engineer shall determine the magnitudeand application of the loads listed below.

A pipe stress analysis shall be completed and all forces shall be provided before anystructural design on pipe racks proceeds. Seismic loads shall be confirmed by the structuralengineer.


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Longitudinal thermal forces shall be considered as uniformly distributed loads over theentire span of the beam applied to the top flange of the pipe support beam.

9.2.4. Long itud inal Beams

All longitudinal beams connecting pipe racks shall be designed for a minimum 10% of thevertical load on the transverse beams with a minimum of 10 kN.

Horizontal load shall be a minimum of 15% of the vertical load from pipe off-takes but shallnot be less than 3 kN. Loads from monorails and platforms etc. shall be considered to actsimultaneously with these loads.

9.2.5. Intermediate beams at tier levels

When determining distribution of load between main pipe rack beams and intermediatetransverse beams at tier levels, consideration of the relative stiffnesss of the beams andsupported pipes shall be taken into account.

9.2.6. Transverse restraint guides

Loadings on restraint guides shall be determined in consultation with the piping engineer.

9.2.7. Cable Trays

Loadings from cable trays shall be determined in consultation with instrument and electricalengineers. As a minimum, the following loads shall be used:

300 wide tray 60 kg/m




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