NPQS C5-10 Structural Steelwork

NPQS C5-10 Structural Steelwork

National Productivity and Quality Specifications (NPQS)

C5-10 Structural Steelwork

Version 1.0


CONTENTS Page 1. 1.1 1.2 1.3 1.4 1.5

GENERAL Scope Related Sections Standards and Technical Reference Trade Preambles Definitions

1 1 1 1 3 6

2. 2.1 2.2

PERFORMANCE REQUIREMENTS Design Brief Loading During Construction

7 7 7

3. 3.1 3.2 3.3 3.4 3.5 3.6

MATERIALS Steel Sections/Elements Welding Consumables Fasteners Profiled Steel Decking Protective Finishes Grout

8 8 9 9 10 10 10

4. 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8

WORKMANSHIP General Storage and Handling Fabrication Bolting Welding Permitted Deviations (PDs) of Fabrication Erection Permitted Deviations (PDs) in Erection

12 12 12 12 14 16 19 26 27

5. 5.1 5.2 5.3 5.4

VERIFICATION AND SUBMISSIONS Submission Procedural Trial and Trial Assemblies Inspection Non-Destructive Testing of Welds

32 32 34 34 34

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1.

GENERAL Read with the General Requirements section, and all other contract documents.

1.1

Scope This section covers the requirements for the fabrication and erection of normal structural steelwork in buildings. It does not cover the use of stainless steel in special structures. This document specifies project specific data to be read in conjunction with section C5-10 of NPQS. All modification and additions noted in this document take precedence over clauses noted in NPQS. Clause references in this document tie with those in C5-10 with the same clause title.

1.2

Related Sections Read this work section in conjunction with the relevant requirements requirements of the other work sections as follows: C5-20

1.3

Protective Works for Structural Steelwork

Standards and Technical Reference 1.3.1

Standard

Unless otherwise agreed by the SO, ensure all of the Works comply with the relevant requirements requirements of the Standards and Codes listed below or referenced in the body of the Specification. Specification. Alternative Standards Standards and Codes may be proposed proposed for approval by the SO, provided it can be demonstrated that the alternative Standards and Codes comply with the requirements requirements of the standards specified. specified. All Standards and Codes Codes quoted are the current version, unless specific year references are noted. Singapore Standards SS 47 470

HotHot-fi fin nish ished str structu ucturral hol hollo low w sect sectio ion ns of of no non-all -allo oy and and fin fine grain ain str structu ucturral steels Part 1: Technical delivery requirements Part 2: Tolerances, dimensions and sectional properties

SS 503

Cold formed welded steel structural hollow sections Part 1 : Technical delivery requirements Part 2 : Tolerances, dimensions and sectional properties

Other Standards ANSI/AWS D1.1-02

Structural welding code. Steel

ASTM E165

Standard test test method for liquid liquid penetrant penetrant examination examination

ASTM E709

Standard guide guide for magnetic magnetic particle particle examination examination

ASTM E747

Controlling quality quality of radiographic radiographic testing testing using wire wire penetrameters penetrameters

BS EN ISO 8981

Mechanical properties of fasteners made of carbon steel and alloy steel. Bolts, screws and studs

BS EN ISO 1461 1461

Hot dip galva galvanise nised d coatings coatings on on fabricate fabricated d iron and and steel steel articles. articles. Specifications and test methods

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BS EN 10024 10024

Hot rolle rolled d tape taperr flan flange ge I secti section ons. s. Tole Tolera rance nces s on shape shape and and dim dimen ensio sions ns

BS EN 10025 10025

Hot rolle rolled d pro produ ducts cts of non-a non-allo lloy y stru structu ctura rall steel steels. s. Tec Techni hnical cal delive delivery ry conditions

BS EN 10029 10029

Toler Toleran ances ces on dimen dimensio sions, ns, shape shape and and mass mass for hot hot rolle rolled d stee steell plat plates es 3mm thick or above

BS EN EN 1005 10051 1

Specif Specifica icatio tion n for for conti continu nuou ously sly hot-r hot-roll olled ed uncoa uncoated ted plate, plate, sheet sheet and and stri strip p of non-alloy and alloy steels. Tolerances on dimensions and shape

BS EN EN 1011 10113 3

HotHot-ro roll lled ed pro produ duct cts s in wel welda dabl ble e fine fine gra grain in str struc uctu tura rall stee steels ls Part 1: General delivery conditions Part 2: Delivery conditions for normalised/ normalised rolled steels Part 3: Delivery conditions for thermomechanical thermomechanical rolled steels

BS EN 10137 10137

Plates Plates and wide wide flat flats s made made of high high yield yield streng strength th struct structur ural al steel steel in the quenched and tempered or precipitation hardened conditions Part 1: General delivery conditions Part 2: Delivery conditions for quenched and tempered steels Part 3: Delivery condition for precipitation-hardened steels

BS EN 10155 10155

Struct Structur ural al steels steels with with imp improv roved ed atmosp atmospher heric ic corro corrosio sion n resis resistan tance. ce. Technical delivery conditions

BS EN EN 1016 10163 3

Specif Specifica icatio tion n for for deli deliver very y requi requirem rement ent for surfa surface ce con condit dition ion of hot hot roll rolled ed steel plates, wide flats and sections Part 1: General requirements Part 2: Plates and wide flats Part 3: Sections

BS EN EN 1021 10210 0

Hot finish finished ed stru structu ctural ral hollo hollow w secti section ons s of non-al non-alloy loy and and fine fine gra grain in stru structu ctural ral steels Part 1: Technical delivery requirements Part 2: Tolerances, dimensions and sectional properties

BS EN 10219 10219

Cold Cold form formed ed welde welded d stru structu ctural ral hollo hollow w secti section ons s of nonnon-all alloy oy and fine fine grai grain n steels

BS EN 10279 10279

Hot rolle rolled d stee steell cha channe nnels. ls. Toler Toleran ances ces on shape shape,, dime dimensi nsion on and and mass mass

BS EN 10034 10034

Struct Structur ural al steel steel I and and H sect section ion.. Tole Tolera rance nce on shape shape and and dim dimens ension ions s

BS EN EN 1005 10055 5

Hot rolle rolled d steel steel equa equall flan flange ge tees tees with with rad radius iused ed root root and and toes. toes. Dime Dimensi nsion ons s and tolerances on shape and dimensions.

BS EN 1005 10056-1 6-1

Struct Structur ural al steel steel equa equall and unequ unequal al leg leg angle angles. s. Dimen Dimensio sions ns

BS EN 10056-2 10056-2

Specifica Specification tion for struct structural ural steel equal equal and and unequ unequal al leg leg angles. angles. Toleran Tolerances ces on shape and dimensions

BS 4-1

Structural steel sections. Specification for hot rolled sections

BS 2583

Podger spanners

BS 36 3692: 92:

ISO ISO met metrric precisi cisio on he hexago xagon n bo bolts, lts, scr screws and nut nuts s – spe specifi cifica cati tion on

BS 41 4190

ISO ISO me metric bl black he hexagon bo bolts, sc screws an and nu nuts – specification

BS 4320

Metal washers for general engineering purposes

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BS 43 4395

Hig High str strength fric fricti tio on grip bol bolts and asso associ ciat ate ed nuts and was wash hers for for structural engineering (metric series)

BS 44 4429

Spec Speciifica ficati tio on for for riggin gging g scr scre ews and tu turnb rnbuckle ckles s fo for ge gener neral en engin gineeri eerin ng lifting purposes and pipe hanger applications

BS 4604 4604

Use Use of high high stre streng ngth th fric fricti tion on grip grip bolt bolts s in in stru struct ctur ural al stee steelw lwor ork k (met (metri ric c seri series es))

BS 4921

Specification for sherardised coatin tings on iron and stee teel

BS 49 4933

ISO ISO me metric bl black cu cup an and co countersunk he head bo bolts an and sc screws wi with hexagon nuts

BS 5531

Code of practice for safety in erecting structural frames

BS 5950

Structural use of steelwork in building Part 1: Code of practice for design. Rolled and welded sections Part 2: Specification for materials, fabrication and erection. Rolled and welded sections Part 4: Code of practice for design of floors with profiled steel sheeting

BS 70 7079

Pre Prepar paratio tion of of ste stee el su substra strate tes s bef befo ore ap applica licati tio on of of pai paint nts s an and rel rela ated ted products. Part A1: Visual assessment of surface cleanliness

BS 7419

Specification for holding down bolts

BS 7644

Direct tension indicators. Part 1: Specification for compressible compressible washers Part 2: Specification for nut face and bolt face washers

BS 76 7668

Weld Welda able str structu ctural ste steels. Hot Hot fin finis ish hed str structu ctural holl hollo ow se sectio ction ns in in weather resistant steels

In the event that the Standards or Codes are partially superseded or become obsolete, refer to the latest edition or the approved substitution for t he relevant clauses. 1.3.2

Technical Reference

When carrying out the works, take guidance from the following technical reference: a.

1.4

UK’s National Structural Steelwork Specification (NSSS), 4th Edition, 2002.

Trade Preambles 1.4.1

Contractor’s Submissions and Proposals

1.4.1.1

Connection Design

Develop the connection design when required as indicated in the PSD. Development Developme nt of the design of connections is *required / not required. required. Engage a PE (civil) to develop the design of the connections based on the structural design drawings. 1.4.1.2

Temporary Works

Engage a PE to plan, design and supervise any necessary temporary supports to ensure the structural steelwork is stable throughout the construction, paying attention to the safe erection of structural steelwork in accordance with BS 5531.

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1.4.2

Shop Drawings

Engage qualified and experienced personnel to prepare coordinated shop drawings for the fabrication and erection of the steelwork. 1.4.3

Qualifications

1.4.3.1

Steel Fabricators

Engage steel fabricators who are accredited under the Structural Steel Fabricators Accreditation Scheme Scheme of the Singapore Singapore Structural Steel Steel Society for the fabrication fabrication works. Refer to the PSD for the required grade of the fabricator. The required grade of steel fabricator is ____. 1.4.3.2

Supervisors

All structural steelwork steelwork and associated associated works are to be undertaken and supervised by appropriately appropriately experienced personnel. Provide evidence of personnel’s personnel’s past experience and certificate to the SO for acceptance prior to commencement of the Works. 1.4.3.3

Welder Qualification

Submit evidence of welders’ competence to the to undertake the specified work. The welders are to be tested to meet the requirements of ANSI/AWS D1.1 Section 4 Part C. The welder’s test is to be conducted and certificates are to be issued by the Independent Independent Inspection I nspection and Testing Agency. 1.4.4

Quality Control Plan

Submit and work to a quality control plan as agreed with the SO. Refer to the General Requirements Requirements section, clause 1.4.10 for guidance. 1.4.5

Accredited Laboratory

Engage a laboratory accepted by the SO and accredited under the Singapore Laboratory Accreditation Accreditation Scheme (SINGLAS) to carry out tests and checks as required by this Specification, including all on site weld tests where applicable. 1.4.6

Independent Inspection and Testing Agency (ITA)

Appoint an independent independent Inspection Inspection and Testing Testing Agency (ITA) when when required as indicated in the PSD. Appointment of of an accredited inspection inspection body is is *required / not required. required. When required, the scope of service of the ITA shall be as follows: S/N

Description

Tick where applicable

1.

Revi Re view ew th the e qu qual alit ity y man manua uals ls,, in insp spe ect ctio ion n & te test st pl plan ans s

2.

Revi Re vie ew fa fabric ica ati tio on and and erec ecti tio on pr proce ced dures

3.

Review Revi ew of we weld ldin ing g pro proce cedu dure re sp spec ecif ific icat atio ion, n, pr pro oce cedu dure re qualification records, welder and welding operator qualification records.

4.

PrePr e-in insp spec ecti tion on me meet etin ing g and and au audi ditt of of fab fabri rica cato torr fac facil ilit itie ies/ s/pl plan ants ts

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5.

Review Revi ew of ma mate teri rial al te test st ce cert rtif ific icat ates es/r /rec ecor ords ds,, ver verif ify y or or in insp spec ectt materials and witness pre-treatment processes, processes, if any

6.

Witnes Witn ess s cu cutti tting ng/e /edg dge e jo join intt pre prepa para rati tion ons, s, ve veri rify fy jo join intt geo geome metr try y and inspect fit-up condition

7.

Verify Veri fy tha thatt weld weldin ing g pro proce cess sses es ar are e car carri ried ed ou outt in ac acco cord rdan ance ce with the approved welding procedures, codes/standards and relevant documents

8.

Perf Pe rfor orm m vis visua uall insp inspec ecti tion on an and d ver verif ify y dim dimen ensi sion onal al re reco cord rds s

9.

Select Sele ct we weld ld jo join ints ts fo forr te test stin ing g & wi witn tnes ess s non non-d -des estr truc ucti tive ve te test stin ing g and assess all results

10.. 10

Witn Wi tnes ess s bla blast stin ing g & ga galv lvan anis isin ing g pro proce cess sses es

11.. 11

Insp In spec ectt pa pain inti ting ng an and d ga galv lvan anis isin ing g wo work rks s

12.. 12

Identi Iden tify fy & ver verif ify y comp comple lete ted d stru struct ctur ural al mem membe bers rs and and wit witne ness ss the the handling of these members onto lorry/truck for delivery to site

13.. 13

Inspec Insp ectt del deliv iver ered ed st stru ruct ctur ural al me memb mber ers s for for dam damag age e due due to handling and transportation

14.. 14

Inspec Insp ectt the the ass assem embl bly y of st stru ruct ctur ural al mem membe bers rs at at erec erecti tion on si site te prior to welding

15.

Verify all wel Verify weldin ding g proc proced edur ure e and and wel welde derr qua qualif lifica icatio tion n reco record rds s at at site

16.. 16

Witn Wi tnes ess s pr proc oced edur ure e tr tria iall of st stud ud we weld ldin ing g pr proc oces ess s

17.. 17

Insp In spe ect al alll we weld lds s & bo bolt lt ti tig ghte ten nin ing g

18.. 18

Sele Se lect ct we weld ld fo forr tes testi ting ng an and d wit witne ness ss si site te ND NDT T

19

Inspec Insp ectt all all rem remai aini ning ng si site te pa pain inti ting ng an and d wit witne ness ss re repa pair irin ing g of of all all protective treatment works

20.. 20

Witn Wi tnes ess s fire firepr proo oofi fing ng moc mockk-up up tes testt as wel welll as lab labor orat ator ory y test tests s

21.. 21

Witn Wi tnes ess s and and ins inspe pect ct the the ap appl plic icat atio ion n of of fire firepr proo oofi fing ng wor works ks

22.. 22

Fina Fi nall ins inspe pect ctio ion n of of all all st stru ruct ctur ural al me memb mber ers s

23.. 23

Review Revi ew all all doc docum umen ents ts and and re reco cord rds s incl includ udin ing g but but not not lim limit ited ed to the following: - Dimensional - Procedures - Testing

Alternatively, Alternatively, the SO may engage the ITA separately. In either of the above cases, make available to the ITA the following: a.

All requested documentation documentati on and a detailed programme to allow the ITA to discharge its duties and to witness significant stages in the fabrication and erection process.

b.

Any instruments instruments or other equipment equipment required required checking checking the accuracy and quality quality of the works.

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1.5

Definitions a.

Design Drawings

Drawings showing the dimensioned layout of the steel structure with the size and material grades of all members, the forces to be developed in their connections and any cambers etc, from which shop drawings are made.

b.

Shop Drawings

Drawings showing all necessary information to fabricate the structural steelwork, including the piece markings with the location in the structure.

c.

Reaming

Forming, shaping, tapering, or enlarging a hole with a reamer.

d.

Faying Surfaces

Surfaces which are tightly or closely fitted.

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2.

PERFORMANCE PERFORMANCE REQUIREMENTS

2.1

Design Brief When carrying out design as described in Clause 1.4.1, ensure the design conforms to the requirements of BS 5950 or other design codes as indicated in the PSD. Design the connections based on forces given in the design drawings. When carrying out design as described in Clause 1.4.1, ensure the design conforms to the requirements of ____.

2.2

Loading During Construction Ensure that the steelwork is adequately braced or restrained to withstand all loadings liable to be encountered during construction without inducing excessive stresses, deflections or distortion in the structure.

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3.

MATERIALS

3.1

Steel Sections/Elements 3.1.1

Material Qualities

Material qualities, dimensions dimensions and tolerances are to comply with the appropriate standard as tabulated below: MATERIAL, DIMENSION AND TOLERANCE STANDARDS Material Qualities Form Non-alloy Fine Q&T Weathering steels grain steels steels steels Universal Beams & Columns Joists Channels

BS 4 -1

Rolled Asymmetric Asymmetric Beams Angles

(4) BS EN (1) 10025

BS EN 10113

BS EN 10137-2 (2)

BS EN 10155

Dimensions

Tolerances

BS 4 -1

BS EN 10034

BS 4 -1

BS EN 10024 BS EN 10279 (4)

BS EN 10056-1

Rolled Tees

BS EN 10055

Split Tees Plates (Reversing Mill) Plates (Cut from Coil) Bars and Rods (3) Wide Flats Hollow Sections (5) (Hot-Finished) Hollow Sections (5) (Cold-Formed) Turnbuckles

BS 4 - 1 -

3.1.2

-

SS 470: Part 1 (BS EN 10210-1) SS 503: Part 1 (BS EN 10219-1) BS 4429

-

BS 7668

-

-

BS EN 10056-2 BS EN 10055 As UB & UC BS EN 10029 BS EN 10051 -

SS 470: Part 2 (BS EN 10210-2) SS 503: Part 2 (4) (BS EN 10219-2 )

Mill Certificates

All steel elements elements are to have the manufacturer’s manufacturer’s mill test certificates indicating indicating compliance with the specified codes. 3.1.3

Surface Condition

3.1.3.1

General Condition

Steel for fabrication is not to be more heavily pitted or rusted than Grade C of BS 7079 Part A1. 3.1.3.2

Rectification of Surface Defects

For hot rolled plates and wide flats, if there are surface imperfections and defects as classified in BS EN 10163-2 Clause 4 (Requirements) revealed during surface preparation, preparation, rectify the t he surface in accordance to BS EN 10163-2 Clause 5 (Repair Procedures).

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For hot rolled sections, if there are surface imperfections and defects as classified in BS EN 10163-3 Clause 4 (Requirements) revealed during surface preparation, rectify the surface in accordance to BS EN 10163-3 Clause 5 (Repair Procedures). For hot rolled hollow sections, rectify t he surface imperfections and defects revealed during surface preparation in accordance to BS EN 10210-1 Clause 6.8 (Surface Condition).

3.2

Welding Consumables Welding consumables consumables for metal arc welding are to comply with ANSI/AWS D1.1 Clause 5.3 (Welding Consumables Consumables and Electrode Requirements). Ensure compatibility between welding consumables and parent materials used for the steelwork.

3.3

Fasteners 3.3.1

Ordinary Bolt Assemblies

Ordinary bolts (full and part threaded length) are to comply with BS 4190 for all grades. Ordinary nuts are to comply with BS 4190 (grade 4 for grade 4.6, 8 for 8.8 and 10 for 10.9). For galvanised or sherardised sherardised bolts use class 10 nuts for 8.8 bolts and class 12 nuts for 10.9 bolts. Black steel washers are to comply with BS 4320 Section 2. 3.3.2

Countersunk Bolt Assemblies

3.3.2.1

Bolts

Comply with BS 4933 for grade 4.6 (cup headed bolts and 90° countersunk head bolts). Comply with BS 4933 (dimensions) and BS EN ISO 898-1 (material) for grade 8.8 bolts. 3.3.2.2

Nuts

Comply with BS 4190 (grade 4) for grade 4.6 bolts. Comply with BS 3692 (grade 8) for grade 8.8 bolts. 3.3.2.3

Washers

Ordinary steel washers (normal diameter series) are to comply with BS 4320 Section 2. 3.3.3

High Strength Friction Grip Fasteners

Bolts, nuts and washers are to comply with: a.

BS 4395-1 for general grade bolts

b.

BS 4395-2 for higher grade bolts

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3.3.4

Lock Nuts for Bolt Assemblies

Comply with BS 3692 or BS 4190 as appropriate. 3.3.5

Holding Down Assemblies

3.3.5.1

Bolts

Comply with BS 7419 for grades 4.6 and 8.8. 3.3.5.2

Nuts

Comply with BS 4190: Grade 4 for grade 4.6 bolts. Grade 8 for grade 8.8 bolts. Class 10 for galvanised or sherardised grade 8.8 bolts. 3.3.5.3

Washers

Comply with BS 4320 Section 2 (normal diameter series) for bolts grades 4.6 and 8.8. 3.3.6

Shear Studs

Proprietary headed studs are to have the following properties: properties:

3.4

a.

Minimum yield strength of 350 N/mm 2

b.

Minimum ultimate tensile strength of 450 450 N/mm2

c.

Elongation of 15% 15% on a gauge length of 5.65 A, where A = area of of test specimen

d.

Diameter and nominal length as noted on the drawings

Profiled Steel Decking Comply with BS 5950-4 Clause 3.1 unless otherwise agreed.

3.5

Protective Finishes 3.5.1

Galvanising Materials

Comply with BS EN ISO 1461. 3.5.2

Sherardised Coatings

Comply with BS 4921. 3.5.3

Metallic Blast Cleaning Abrasives

Comply with BS 7079-E2 for chilled iron grit. Comply with BS 7079-RE3 for cast steel grit. 3.5.4

Surface Coatings

Refer to Section C5-20, clause 3.0 for all paints and other coatings.

3.6

Grout Grout is to comply with BS 5950-2 Section 2.5. Grout around anchor bolts under base plates and between steel plates and concrete surface is to have a minimum compressive strength at 28 days of 40 N/mm 2. Version 1.0 Page 10


Proprietary grouts are not to contain high alumina cement.

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4.

WORKMANSHIP

4.1

General 4.1.1

Traceability

All steel elements elements are to be identified identified and traceable traceable to the manufacturer’s manufacturer’s material/mill test certificates. 4.1.2

Marking

Mark all pieces so that they can be identified at all stages of fabrication. Mark completed components in locations that will not be covered up by other material after erection to avoid confusion. Hard stamping may be used other than where specified in the PSD. Hard stamping may be used other than at the following areas: a. _____ b. _____ Keep areas of steelwork free of all markings where so required on the Drawings.

4.2

Storage and Handling Prepare and comply with proper storage and handling procedures in approved method statement to ensure achievement of the desired quality and to minimise damage to the steelwork. 4.2.1

Holding Areas

Lay steel in separate holding areas and keep clean. 4.2.2

Storage

Adequately support support steel clear of of the ground. Keep Keep clean and do do not allow water water to accumulate on components. Protect steel against corrosion. Ensure individual piece markings are visible when members are stacked. 4.2.3

Handling

Plan and carry out bundling, packing, handling and transport in a manner designed to prevent permanent distortion to the steelwork and minimise damage to any protective coating. 4.2.4

Storage and Drying of Welding Consumables

Store and protect welding consumables that have been removed from the original package so that the welding properties properties are not affected. Carry out drying or re-baking, where necessary, in accordance with the manufacturer’s manufacturer’s recommendations. recommendations.

4.3

Fabrication Prepare and comply with proper fabrication procedures to SO’s acceptance, to ensure achievement of the desired quality. Version 1.0 Page 12


4.3.1

Cutting

Comply with BS 5950-2 Clause 3.3 (Cutting). Cut and shape steel by sawing, shearing, cropping, cropping, nibbling, plasma or laser cutting and thermal or flame cutting. Thermal cutting are not permitted at the areas indicated in the PSD. Thermal cutting are not permitted at the following areas: a. ____ b. ____ 4.3.1.1

Hand Flame Cutting

Use only where it is impractical to use machine flame cutting. 4.3.1.2

Flame Cut Edges

Flame-cut edges that are free from significant irregularities require no further treatment other than dressing as specified in 4.3.3(Dressing). 4.3.3(Dressing). 4.3.2

Holing

Comply with BS 5950-2 Clause 3.4 (Holing). 4.3.2.1

Forming

Drill, punch, plasma or laser cut and thermal or flame cut round holes for fasteners. Thermal holing or full size hole punching are not permitted at the areas indicated in the PSD. Thermal holing or full size hole punching are not permitted at the following areas: a. ____ b. ____ 4.3.2.2

Matching

Ensure all matching holes are formed such that fasteners can be inserted freely through the assembled members at right angles to the contact faces. Drifting to align holes may be used provided it neither enlarges nor distorts the holes. 4.3.2.3

Drilling through Multiple Thickness

Tightly clamp the separate parts before drilling and remove any burrs after separating the parts. 4.3.2.4

Punching Full Size

Punching of full size holes is permitted when all the following conditions are satisfied: a.

The tolerance tolerance on distortion of the punched punched hole hole does not exceed that specified; specified;

b.

The holes holes are free free of burrs burrs which would prevent prevent solid seating of of the parts parts when tightened;

c.

The thickness thickness of the material is is not greater greater than 30mm, nor nor greater than the diameter of the hole being punched;

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d.

In spliced spliced connections connections when the holes holes in mating mating surfaces surfaces are punched in in the same direction and the splice plates marked to show the assembly faces, if packed separately.

4.3.2.5

Punching and Reaming

When the conditions in 4.3.2.4 is not satisfied, punching is still permitted provided that the holes are punched at least 2mm less in diameter than the required size and the holes are then reamed to the full diameter after assembly. 4.3.3

Dressing

4.3.3.1

Removal of Burrs

Dress cut edges or holes to remove dross, burrs, irregularities irregularities and protruding edges. If holes are drilled through components that are clamped together not intended to be separated after drilling, removal of burrs is not required. 4.3.3.2

Dressing of Sharp Edges

Dress all sharp edges. A 90° rolled, sheared sheared or machined machined cut edge requires requires no further treatment. treatment. 4.3.4

Curving and Straightening

Curve or straighten components during fabrication using mechanical means or the local application of heat. 4.3.4.1

Heating

Control the temperature carefully and do not let the temperature exceed 650°C. 4.3.4.2

Inspection

After the process is complete, complete, visually visually inspect all welds welds within the area of curving or straightening. straightening. Carry out non-destructive testing of welds, where directed.

4.4

Bolting 4.4.1

Hole Sizes for Bolting

4.4.1.1

Ordinary and HSFG Bolts

a.

For bolts ≤ 24mm diameter, hole sizes are to be bolt diameter +2mm.

b.

For bolts > 24mm diameter, hole sizes are to be bolt diameter +3mm.

4.4.1.2

Holding Down Bolts

Hole sizes are to be bolt diameter +6mm with sufficient clearance to ensure the bolt can be accommodated through the base plate when adjusted. 4.4.1.3

Fitted Bolts

Clearance of bolt in hole is not to exceed 0.3mm. 4.4.2

Ordinary Bolted Assemblies

4.4.2.1

Make-up of Bolt Assemblies

Refer to Clause 3.3.1(Ordinary Bolt Assemblies) for strength grade combination of bolt/nuts/washers.

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4.4.2.2

Condition of Bolts

Bolt assemblies are to be in such condition immediately before installation that the nut turns freely on the bolt. 4.4.2.3

Differing Grades of Bolts

Unless otherwise agreed agreed by the SO, do not use different bolt grades of the same diameter in the same structure.

4.4.2.4

Bolt Length

The length of bolt is to be such that at least one clear thread shows above the nut after tightening, and at least one thread plus the thread run out is clear between the nut and the unthreaded shank of the bolt. 4.4.2.5

Washers

Use at least one washer placed under the nut or bolt head being rotated in each bolt assembly where the rotation might damage the surface protective treatment on the members being connected. Use a plate or heavy duty washer under the head and nut where the members being connected have oversize or slotted holes. 4.4.2.6

Taper Washers

Place under bolt heads and nuts bearing on surfaces sloping 3 ° or more from a plane at right angles to the bolt axis. 4.4.2.7

Galvanised Nuts

Check after galvanizing to ensure free running on the bolt. Re-tap nuts, if necessary, to ensure satisfactory tightening. 4.4.2.8

Tightening

Use power tools or by hand using appropriate spanners to BS 2583. 4.4.2.9

Locking of Nuts

Secure nuts used in connections subject to vibration or reversal of stresses to prevent loosening. If not specified on the drawings, drawings, include the proposed method method in the erection details. 4.4.2.10

Fit-up Using Ordinary Bolt Assemblies

Draw connected parts firmly together. If there is a remaining gap more than 2mm, which may affect the integrity of the joint, take the joint apart and insert a pack of the same steel material. 4.4.2.11

Reaming

Reaming may be used where the connection design allows allows the use of larger diameter holes and bolts in cases where drifting would distort the steelwork. 4.4.3

High Strength Friction Grip Fasteners

4.4.3.1

Make-up of Bolt Assemblies

Refer to Clause 3.3.3(High Strength Friction Grip Fasteners) for strength grade combination of bolt/nuts/washers. bolt/nuts/washers. Place the hardened washer under the nut or head being turned.

Version 1.0 Page 15


4.4.3.2

Tightening

Use high strength friction grip bolts in compliance with BS 4604-1 or 2. Use the torque control method, the part-turn method or direct tension indicators in accordance with the manufacturer’s recommendations for tightening in compliance with BS 4604-1. 4.4.3.3

Calibration of Torque Equipment

Calibrate torque devices at least once each shift. Recalibrate where necessary in accordance with BS 4604. 4.4.3.4

Discarded Bolt Assemblies

If after tightening, a bolt or nut is slackened off for any reason, discard the complete bolt assembly and do not re-use in the Works. 4.4.3.5

Fit-up Using High Strength Friction Grip Fasteners

Draw connected parts firmly together with all bolts partially tightened. tightened. If there is a remaining gap, take the joint apart and insert a pack of the same steel material before continuing tightening. 4.4.3.6

Reaming

Reaming may be used where the connection design allows allows the use of larger bolts in cases where drifting would distort the steelwork. Demonstrate by calculation that the connection is adequate for the specified forces. 4.4.3.7

Faying Surfaces for HSFG Fasteners

Remove all mill-scale from the faying surfaces of friction grip joints. Ensure the faying surfaces of friction grip joints are free of distortion, deformities or contaminants, contaminants, which may reduce the slip factor below the design value. 4.4.4

Slotted Holes Bolts

Where slotted holes are provided for movement connections ensure the joint is free to move. 4.4.5

Holes in Hollow Sections

Seal bolt holes and vent holes in hollow sections to prevent the ingress of moisture. If not specified on the design drawings, show the proposed method on the shop drawings.

4.5

Welding 4.5.1

Welding Processes

Processes for Shielded metal arc welding (SMAW), submerged arc welding (SAW), gas metal arc welding (GMAW) except GMAW-S, short circuiting transfer and flux cored arc welding (FCAW) which conform to all of the requirements of ANSI/AWS D1.1 Section 3 are deemed as pre-qualified pre-qualified and accepted for use without performing the Welding Procedure Specifications (WPS) Qualification Tests. Gas tungsten arc welding (GTAW), electro-slag welding (ESW) or electro-gas welding (EGW) and gas metal arc welding - short circuiting transfer (GMAW-S) are to conform to all of the requirements of ANSI/AWS D1.1 Section 4.

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4.5.2

Welding Supervisor

Carry out welding under the direction of a welding supervisor with appropriate qualifications. 4.5.3

Welding Procedures Specifications

4.5.3.1

Preparation

Prepare Written Welding Procedure Specification (WPS) in accordance with ANSI/AWS D1.1 Section Section 4 Part B for acceptance acceptance by the Independent Independent Inspection and Testing Agency. 4.5.3.2

Procedure Tests

All procedure tests conducted are are to be witnessed by by the Independent Independent Inspection and Testing Agency. 4.5.3.3

Availability of Welding Procedure Specifications

Make WPS available to the welder, the SO and the Independent Inspection and Testing Agency prior to the commencement commencement of the works. 4.5.3.4

Inspection and test plans

Submit all inspection and test plans for SO’s acceptance prior to carrying out welding works. 4.5.4

Assembly

4.5.4.1

Fit-up

Fit up joints to the dimensional accuracy in accordance with the following: a.

ANSI/AWS D1.1 D1.1 Clause Clause 3.9 (Fillet Weld Weld Requirement) Requirement) for Fillet Welding

b.

ANSI/AWS D1.1 Clause Clause 3.11 3.11 (Common (Common Requirements Requirements of Partial and Complete Complete Joint Penetration Groove Welds) and Clause 3.12 (Partial Joint Penetration Requirements) Requirements) for Partial Penetration Butt Welding.

c.

ANSI/AWS D1.1 Clause Clause 3.11 3.11 (Common (Common Requirements Requirements of Partial Partial and Complete Joint Penetration Groove Welds and Clause 3.13 (Complete Joint Penetration Requirements) Requirements) for Partial Penetration Butt Welding.

4.5.4.2

Temporary Welds and Tack Welds

Temporary welds are subject to the same welding procedure requirements requirements as the final welds. Remove the temporary welds unless otherwise agreed by the SO. Make flush the surface with the original surface after the removal. Tack welds are subject to the same quality requirements as the final welds, with the following exceptions: a.

Preheat is is not mandatory mandatory for single-pass tack welds welds which are re-melted re-melted and incorporated into continuous submerged arc welds.

b.

Discontinuities, Discontinuities, such as undercut, undercut, unfilled craters and porosity need need not be removed before the final submerged arc welding.

c.

Tack welds, welds, which are incorporated incorporated into into the final final weld, weld, are to be made with electrodes meeting the requirements of the final welds and are to be cleaned thoroughly. Multiple-pass Multiple-pass tack welds are to have cascaded ends.

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Remove tack welds, which are not incorporated into the final weld, unless otherwise agreed by the SO. 4.5.4.3

Control of Distortion and Shrinkage

Procedure and sequence of welding is to be in accordance with ANSI/AWS D1.1 Clause 5.21 to minimise distortion and shrinkage. 4.5.4.4

Temporary Attachments

Welding of temporary attachments required for fabrication or erection is to be carried out in accordance with the requirements for permanent welds. Remove after use where required by flame cutting or gouging at a point not less than 3mm from the surface of the parent metal. Grind flush and inspect the area visually. Where the parent metal is more than 20mm thick, check by magnetic particle testing method inspection using the acceptance criteria stipulated in Clause Error! Reference source not found.(Non-Destructi found.(Non-Destructive ve Testing of Welds). Do not remove temporary attachments by hammering. 4.5.5

Shear Stud Welding

4.5.5.1

Method

Fix shear studs in accordance with the manufacturer’s recommendations recommendations for materials, procedures and equipment. 4.5.5.2

Welding Procedure Trial

Where required, carry out welding procedure trial of studs to demonstrate the suitability of the proposed welding system and equipment before commencement of the work. The trial is to use the materials and procedures procedures proposed for the works. Test a minimum of ten studs in the trial. During the work, at the commencement of each shift, each welder is to undertake a minimum of two trial welds. 4.5.5.3

Visual Inspection

Visually inspect all studs. They are to exhibit full 360 degree ‘flash’ with no evidence of undercut into the stud base. 4.5.5.4

Bend Test

Subject studs to bend tests at locations agreed with the SO. Test at least 5% of studs and not less than two per beam. Bend the head of the stud by striking the head of the stud to an angle of approximately 30° from their original axis with a hammer. Under this test the weld is to show no visible signs of cracking or lack of fusion. Do not straighten any studs so tested. 4.5.5.5

Defective Studs

Replace any studs with defective welding and re-test as above. Where defective studs are removed check the surface as specified in 4.5.5.3 above.

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4.5.6

Removal of Slag

Remove slag by light hammering, wire brushing or other means that do not deform the surface of the weld.

4.6

Permitted Deviations (PDs) of Fabrication 4.6.1

PDs in Rolled Components After Fabrication

4.6.1.1

Cross Section After Fabrication

In accordance with the appropriate standards given in clause 3.1.1(Material Qualities) 4.6.1.2

Squareness of Ends not Prepared for Bearing

PD = D/300, where D is the depth of the section.

= D/300

D

Plan or Elevation of End

4.6.1.3

Squareness of Ends Prepared for Bearing

PD = D/1000, where D is the depth of the section and the deviation is measured relative to the longitudinal axis of the member. = D/1000 90°

D Plan or Elevation

4.6.1.4

Straightness

PD of a member from a straight line drawn between adjacent points of subsequent effective lateral restraint = 3mm or L/1000, whichever is greater, where L is the distance between restraints. L

= L/1000 or 3mm whichever is the greater

4.6.1.5

Camber

PD from specified or proposed camber at mid-length = 6mm or L/1000, whichever is greater, where L is the length of the member.

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Deviation L Deviation = L/1000 or 6mm whichever is the greater

4.6.1.6

Length

PD after cutting, measured on the centre line of the section or on the corner of angles = 2mm.

L±

= 2mm

4.6.2

PDs of Fabricated Components

4.6.2.1

Position of Fittings

PD from the intended position for fittings and components whose location is critical to the force path = 3mm. = 3mm

4.6.2.2

Position of Holes

PD from the intended position of hole or group of holes = 2mm. = 2mm

4.6.2.3

Punched Holes

Distortion caused by a punched hole is not to exceed D/10 or 1mm, whichever is greater, where D is the nominal hole diameter.

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D

= D/10 or 1mm whichever is the greater

4.6.2.4

Sheared or Cropped Edges of Plates or Angles

Deviation from a 90° edge is not to exceed t/10 where t = plate thickness.

t = t/10

4.6.2.5

Flatness

Gaps in joints that depend on contact bearing when assembled during fabrication are not to exceed 0.75mm and are to be less than 0.25mm over 50% of the length of contact of the section.

=

4.6.3

PDs in Plate Girder Sections

4.6.3.1

Depth

PD measured on centre line = ± 4mm.

D±

= 4mm

4.6.3.2

Flange Width

For flange width B < 300mm, PD = ±3mm. For flange width B ≥ 300mm, PD = ±5mm.

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Bw ±

B w or B n < 300 = 3mm B w or B n _ > 300 = 5mm

Bn ±

4.6.3.3

Squareness of Sections

For flange width B, PD on out of squareness = B/100 or 3mm, whichever is greater. B Flange width

= B / 100 or 3mm whichever is the greater

4.6.3.4

Web Eccentricity

PD on intended position of web from one edge of flange = ± 5mm. b ±

4.6.3.5

= 5mm

Flanges

For flange width B, PD on out of flatness = B/100 or 3mm, whichever is greater. B Flange width

= B/100 or 3mm

4.6.3.6

Top Flange of Crane Girder

PD on out of flatness where rail seats = 1mm. w = Rail width + 20mm w w

= 1mm

4.6.3.7

Length

PD on length on centre line = ± 3mm.

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L± = 3mm

4.6.3.8

Flange Straightness

PD on straightness of individual flanges = L/1000 or 3mm, whichever is greater, where L is length.

L = L/1000 or 3mm whichever is the greater

4.6.3.9

Curve or Camber

PD on intended curve or camber at mid-length of curved portion = L/1000 or 6mm, whichever is greater, where L is length and deviation is measured with web horizontal.

Deviation L Deviation = L/1000 or 6mm

4.6.3.10

Web Distortion

PD on distortion on web depth (or gauge length) = d/150 or 3mm, whichever is greater, where d is depth of web. gauge length = web depth d = d/150 or 3mm

4.6.3.11

Cross Section at Bearings

PD on squareness of flanges to web = D/300 or 3mm, whichever is greater, where D is depth of section.

D = D/300 or 3mm which hichev ever er is the the reat reater er

4.6.3.12

Web Stiffeners

PD on straightness of stiffener out of plane with web after welding = d/500 or 3mm, whichever is greater, where d is depth of stiffener. Version 1.0 Page 23


d = d/500 or 3mm whichever is the greater

PD on straightness of stiffener in plane with web after welding = d/250 or 3mm, whichever is greater, where d is depth of stiffener.

d = d/250 or 3mm whichever is the greater

4.6.4

PDs in Box Sections

4.6.4.1

Plate Widths

For Bf or Bw < 300mm, PD = ±3mm, where B f , Bw are flange width and web depth respectively. For Bf or Bw ≥ 300mm, PD = ± 5mm. B ± f B ± w B or B < 300 w f = 3mm B or B _ > 300 w f = 5mm

4.6.4.2

Squareness

PD on squareness measured at diaphragm positions = D/300, where D is section depth. = D/300

D

4.6.4.3

Plate Distortion

PD on distortion on width or gauge length = w/150 or 3mm, whichever is the greater, where w is depth of web.

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gauge length = width, w w = w/150 or 3mm whichever is the greater

4.6.4.4

Web or Flange Straightness

PD on straightness of individual web or flanges = L/1000 or 3mm, whichever is the greater, where L is f ull length.

L = L / 1000 or 3mm whichever is the greater

4.6.4.5

Web Stiffeners

PD on straightness in plane with plate after welding = d/500 or 3mm, whichever is the greater, where d is depth of web.

d = d / 500 or 3mm whichever is the greater

PD on straightness out of plane to plate after welding = d/250 or 3mm, whichever is the greater, where d is depth of web.

d = d / 250 or 3mm whichever is the greater

4.6.4.6

Length

PD on length measured on centre line = ± 3mm.

L± = 3mm

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4.6.4.7

Curve or Camber

PD on deviation from intended curve or camber at mid-length of curved portion when measured with the un-cambered side horizontal = L/1000 or 6mm, whichever is the greater, where L is length of the curved portion. Deviation L Deviation = L / 1000 or 6mm whichever is the greater

4.7

Erection 4.7.1

General

Prepare and comply with proper erection procedures to SO’s acceptance, to ensure achievement achievement of the desired quality and safety, paying attention t o site conditions, constraints and restrictions. 4.7.2

Erection Loads

Ensure that the structure is not overloaded by stacking of materials. 4.7.3

Temporary Supports

Any temporary supports supports used may may be removed after the the structure has been been lined, levelled and plumbed, provided sufficient components have been erected and secured to ensure the overall structure remains stable under the worst anticipated conditions of loading. 4.7.4

Alignment

Align each part part of the structure as soon soon as practicable practicable after erection. Do not make permanent connections between members until the structure has been sufficiently aligned, levelled, plumbed plumbed and temporarily connected so that members will not be displaced during subsequent subsequent erection or alignment of the remainder of the structure. 4.7.5

Temperature Adjustment

Take due account of the effects of temperature on the structure and measuring equipment when measurements measurements are made for setting-out and erection, and for dimensional dimensional checks carried out subsequently. Adopt 30°C as as the reference temperature temperature unless otherwise otherwise agreed agreed . 4.7.6

Site Welding

Carry out site welding only by agreement with the SO or as shown on the design drawings. Carry out all site welding in accordance with clause 4.5(Welding) above. Do not carry out site welding in inclement weather unless adequate weather protection is provided for welders and materials.

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4.7.7

Foundation Bolts

Hold foundation bolts firmly in position during all setting-in operations. Protect bolts, threads and nuts against damage, corrosion and contamination contamination at all stages of construction. Keep pockets formed around foundation bolts clean and free from all extraneous matter. Use templates to set in the holding-down bolts. 4.7.8

Packs and Wedges

Plumb and level columns using steel packs and wedges of adequate strength and stiffness, and not larger than necessary for the purpose. Where packings are to be left in position and subsequently grouted, place them such that they are totally enclosed by the grout. 4.7.9

Grouting

Carry out grouting in accordance with BS 5950-2 Clause 6.3. Do not carry out grouting under column base plates until a sufficient portion of the structure has been aligned, levelled, plumbed and adequately braced. Immediately before grouting, clean the space under the column base plates t o be free of all extraneous matter. Prepare, mix and place proprietary grout in accordance with the manufacturer’s manufacturer’s recommendations. 4.7.10

Profiled Steel Decking

Install in accordance with manufacturer’s recommendations, recommendations, including the provision of edge trims, temporary supports, lapping, etc.

4.8

Permitted Deviations (PDs) in Erection Erect steelwork within the PDs in the following clauses. 4.8.1

Receiving Structures and Connections

Ensure that structures by others to which the steelwork attaches is constructed within the anticipated PDs before commencing steel erection. Where components and fixings are cast in by others ensure that they are also within the anticipated PDs before commencing steel erection. Inspect for position and level in good time before the planned start of steelwork erection. In the event of any discrepancies found, notify the SO, propose and correct the discrepancies. 4.8.2

PDs of Holding Down Bolts

4.8.2.1

Bolts or Bolt Groups with Allowance for Adjustment

a. Bolt level:

+25/-5mm.

b. Minimu Minimum m cleara clearance nce::

25mm 25mm at top of concre concrete te

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c. Bolt centro troid:

±10mm from specified position at top of concrete. te.

= ± 10 mm from specified position at top of concrete =

+ 25 mm - 5 mm bolt level 25 mm minimum clearance at top of concrete

4.8.2.2

Bolts or Bolt Groups with No Allowance for Adjustment

a. Bolt level:

+45/-5mm.

b. Bolt centro troid:

±3mm from specifie fied position at top of concrete.

= ± 3 mm from specified position at top of concrete =

4.8.2.3

+ 45 mm - 5 mm bolt level

Bolts or Bolt Groups Cast into Walls (No Allowance for Adjustment)

a. En End of bolt:

+45/-5mm.

b. Bolt centroid:

±3mm position in plan and elevation.

=

+ 45 mm - 5 mm bolt level = ± 3 mm position in plan and elevation

4.8.3

PD of Level of Base Plate

PD of level of column base plate = 5mm. 4.8.4

PDs of Erected Components

4.8.4.1

Position of Columns at Base

PD of section centreline from the specified position = 10mm.

= 10mm

4.8.4.2

Overall Plan Dimension

PD on length or width = 20mm for L < 30m and [20 + 0.25 (L-30)] mm for L ≥ 30m, where L is the specified overall dimension in metres.

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4.8.4.3

Plumb of Single Storey Columns

PD of top relative to base = ± h/600 or 5mm, whichever is greater, on main axes, excluding portal frame columns, where h is the storey height.

H

H

= ± H/600 or 5 mm whichever is greater Max = ± 25mm

4.8.4.4

Plumb in Multi Storey Columns

PD in each storey of column = h/600 or 5mm, whichever is greater, where h is the storey height. PD of column at top storey relative to specified position at base plate = 50mm maximum. H

h = storey height h

h = ± h/600 or 5 mm whichever is greater H = 50mm maximum

4.8.4.5

Alignment of Adjacent Perimeter Columns

PD of one column relative to the next on a line parallel to the grid line = 10mm when measured at the base or splice level. critical face of columns

= 10 mm

4.8.4.6

Gap Between Bearing Surfaces

PD = (D/1000 +1) mm where D is the dimension along the bearing surface.

D

= (D / 1000) + 1 mm D

4.8.4.7

Level of Beams

a. PD of two or more beams meeting at a column = ± 5mm.

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Specified Level

= ± 10mm

b. PD on level of beam at its ends = 5mm.

= ± 5mm

c. PD on level of adjacent beams within a distance of 5m = ± 5mm.

= ± 5mm

d. PD from specified specified level of beam at at supporting column = ± 10mm. Floor Level h Floor Level h<3m,

= 5mm

h<3m h<3m

= h/600 h/600

e. PD of beam relative to adjacent adjacent beam beam above or or below = 5mm for h < 3m and h/600 for h ≥ 3m, where h = storey height in m. 4.8.4.8

Plumb of Crane Gantry Columns

PD = ± Hc/1000 or 5mm, whichever is greater to a maximum of ± 25mm.

H c

= ± Hc /1000 or 5mm 5mm whichever is greater Max = ± 25mm

4.8.4.9

Crane Gantries Gauge of Rail Tracks

PD from true gauge = ± 10mm. Version 1.0 Page 30


G+H

= ± 10mm

4.8.4.10

Joints in Gantry Crane Rails

a. PD on rail surface surface across across joint joint = 0.5mm.

= 0.5mm

b. PD on rail edge edge alignment alignment across joint = 1mm.

= 1mm

4.8.4.11

Profile Steel Floor Decking

PD of dimension between deck edge trim and perimeter beam = ± 10mm for deck span in either direction.

x±

Actual beam CL

Grid line

Generic profile deck may span either direction

= ± 10mm

4.8.5

Deviations Exceeding PDs

Inform the SO as soon as possible if checks show that the deviation in position of the steelwork as erected exceeds the PDs given above. Propose and carry out remedial measures as required.

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5.

VERIFICATION AND SUBMISSIONS

5.1

Submission 5.1.1

Design Submission

When required in Clause 1.4.1, submit to the SO for acceptance calculations calculations and drawings for the connection details details within time as directed by the SO prior to commencement commencement of the Works. 5.1.2

Shop Drawings

Submit to the SO for acceptance complete and coordinated shop drawings within time as directed by the SO prior to commencement commencement of any works. Include all details of the steel structures incorporating at least the following information: information: a.

Number of pieces of steel sections

b.

Dimensions

c.

Tolerances

d.

Connection details

e.

Bearing locations and details

f.

All other fabrication and erection details

5.1.3

Method Statement

Provide a detailed method statement to the SO for acceptance within directed time prior to commencement of any works. Include at least the following information: information: a.

A site plan plan showing showing the work layout layout area, position and and type of cranes, access routes, datum level, setting-out lines, storage area, etc.

b.

Fabrication procedure/manual, procedure/manual, locations locations (local (local and/or and/or overseas), overseas), list list of subcontractors/suppliers subcontractors/suppliers and their scope of works, quality assurance system, etc.

c.

Storage and handling.

d.

Maximum size of structural structural steel steel components components that can be delivered to the site. site.

e.

Assembly of structural members on on the ground ground level level before erection, where where partial or complete fabrication work is required on site.

f.

Sequence and method of erection erection and assembly of structural structural members taking into account the site conditions, site constraints, site restriction and interface with other trades.

g.

Detailed drawings and calculations calculations for temporary works.

h.

Details of of proposed site inspection inspection systems systems by the Accredited Inspection Inspection Body. Body.

i.

Details of staging, staging, platforms platforms and weather protection where site welding welding is to take place.

j.

Remedial procedures procedures for damaged damaged steelwork steelwork during fabrication, fabrication, transportation, transportation, storage, handling and erection.

k.

Safety procedures procedures for handling handling and and erection erection of steelwork on site. site.

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5.1.4

Construction Information

Provide the following information within time as directed by the SO prior to commencement commencement of the Works: a. Welder qualification qualification records, records, welding procedure records, stud welding procedure records. b. Details of welding welding procedures procedures in accordance with ANSI/AWS D1.1 for all welds, including tack and sealing welds. c. Details of proposed proposed shop shop inspection inspection system by the Independent Independent Inspection and Testing Agency. 5.1.5

Programme

Provide a detailed programme to show the planned timing of the various items of work to be done within time as directed by the SO, including: a. Preparation and submission submission of construction construction information information b. Order and delivery of materials materials c. Fabrication d. Application of protective coatings e. Transportation to site f.

Erection

Include in the programme, the time required for all procedural trials, inspection and testing, and trial assemblies. 5.1.6

Material Certificates

Submit to the SO for acceptance, material certificates duly verified by the Independent Independent Inspection and Testing Agency within time as directed by the SO prior to commencement of any work. 5.1.6.1

Mill Certificates

Provide mill certificates for every batch of supply confirming compliance compliance with the specified standards before the supply of material to the works. 5.1.6.2

Test Certificates/Reports Certificates/Reports for Bolts and Inserts

Provide test certificates/reports and demonstrate by testing on 2% of actual materials used that bolts and inserts used in the Works conform to the specified requirements. 5.1.7

Inspection by ITA

Submit all reports from the Independent Inspection and Testing Agency to SO periodically as agreed with the SO. 5.1.8

As-built Drawings

Submit as-built drawings to the SO for record upon completion of the Works. Include information on all element type, sizes, position including deviation exceeding exceeding the permitted PD if any, connection and assembly details, and protective works applied if any.

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5.1.9

Quality Control Manual

Submit a Quality Manual containing a QA/QC programme programme for the Works to the SO for acceptance within directed time frame. The Quality Manual is to include at least information on the following: a. Quality policy b. Organisation charts and responsibilities responsibilities c. Internal quality control and audits d. Facilities Facilitie s and equipment e. Calibration and testing of equipment equipment f.

Testing and inspection procedures

Subcontractors and suppliers

5.2

Procedural Trial and Trial Assemblies Carry out procedural trial and trial assemblies as agreed with the SO, including tests on material and workmanship in accordance with the Specification, prior to commencement commencement of the t he Works. Give adequate period of notice as agreed with the SO. Keep records of all tests and make them available to the SO and the Independent Inspection and Testing Agency for examination throughout the duration of the Works.

5.3

Inspection 5.3.1

Inspection of Accuracy of Fabrication and Erection

Provide inspection reports in agreed batches endorsed by the Independent Inspection and Testing Agency, verifying that the fabrication and erection of the works comply with the specified requirements. 5.3.2

Visual Inspection of Welds

Carry out visual inspection over the full lengths of all welds prior to any NonDestructive Testing (NDT). Immediately examine any welds that will be covered up before loss of access. The acceptance criteria for visual inspection are to be in accordance with ANSI/AWS D1.1 Table 6.1.

5.4

Non-Destructive Non-Destructive Testing of Welds 5.4.1

Scope of Inspection

Carry out Non-Destructive Testing as tabulated below unless otherwise agreed. Inspection requirements requirements may be reduced by agreement with the SO based on satisfactory performance in the initial tests. Full Full Penet enetra rattion ion But Buttt Wel Weld ds

Part Partia iall Pen Pene etrat tratio ion n But Buttt Wel Welds ds

Version 1.0 Page 34


Examples:

Examples:

MT / PT

Thickness

All thicknesses

All thicknesses

Frequency

50% (site welds 100%)


UT / RT

Thickness

tmax

tmax

Frequency


≥ 3

mm

≥ 3

mm


Fillet Welds Examples:

MT / PT

UT / RT

5.4.2

Thickness

Fillet weld size ≥ 3 mm

Frequency Frequency

10% (site (site welds welds 100% 100% but but longitudinal longitudinal welds welds 0.5m 0.5m in each each 10m 10m or part part thereof)

Thickness

Fillet weld size ≥ 20 mm

Frequency Frequency

20% (site (site welds welds 100% 100% but but longitudinal longitudinal welds welds 1.0m 1.0m in each each 10m 10m or part part thereof)

As directed by SO

Hold Time Prior to NDT

For welds subject to NDT, carry out the testing at least 24 hours after the completion of the welds. For quenched and tempered steel, carry out NDT not less than 48 hours after the completion of the t he welds. 5.4.3

Magnetic Particle Testing (MT) and Penetrant Testing (PT)

Where magnetic particle testing (MT) is required in accordance with Clause 5.4.1(Scope of Inspection), the procedure and technique are to be in accordance with ASTM E709. If Magnetic Particle testing is impractical, use Penetrant testing in accordance with the procedure and technique given in ASTM E165. 5.4.4

Ultrasonic Examination (UT)

Where ultrasonic testing is required in accordance with Clause 5.4.1(Scope of Inspection), the procedure and technique are to be made in accordance with ANSI/AWS D1.1 Section Section 6 Part F. If ultrasonic testing is impractical, for example when the plate thickness is less than 8mm, use radiographic testing in accordance with the procedure and technique given in ANSI/AWS D1.1 Section 6 Part E.

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5.4.5

Radiographic Examination (RT)

Where radiographic testing is required in accordance with Clause 5.4.1(Scope of Inspection), the procedure and technique are to be in accordance with ASTM E94 and ASTM E747. 5.4.6

Acceptance Criteria and Corrective Actions

Acceptance criteria criteria are to be in accordance accordance with ANSI/AWS D1.1 Section Section 6 Part C. Propose corrective actions actions to the SO for acceptance if the welds do not conform to the acceptance criteria. 5.4.7

Weld Test Records

Record the results of all visual inspections and non-destructive non-destructive testing and make all records available for inspection.

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NPQS C5-10 Structural Steelwork

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