50723682 steel design to bs5950 essential data

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s The Steel Construction Institute. Its aim is to promote the proper and effective use of steel— m construction.

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This guide has been published Inassociation with the following:

British Steel General SteeLs -Sections

British Steel Sections produces and markets structural steel sections to BS4 and BS4848, Parts 4 and 5 i.e.pnncipally universal beams, columns and piles, joists, channels, angles and T sections. A Regional AdvisoryStructural Engineering Service is maintained to help specifiers with any problems relevant to structural steelworkdesign and to provide a point of contact with the sales functions and Technical Services. A series of publicationsareavailable ealing with he steel products and their use.

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British Steel Strip Products produces wide steel strip in various sizes and thicknesses for manufacture nto a verywide range of construction products. Although some use is made of hot rolled coil in this connection, the majority ofthe production is supplied for construction purposes as metal (zinc, aluminium) coated, pre-finished paint coated orlaminated with PVC film. The Technical Advisory Services gives information and advice on the products of BS StripMill Products.

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SCI PUBLICATION 070

SteelworkDesignGuide to BS 5950

Volume 4

Essential Data for Designers

British LibraryCataloguing n Publication DataSteelwork design guide to BS 5950Volume 4: Essential data for designers1. Steel structures. DesignI. Steel Construction Institute624.1821

ISBN 1 870004 00 0 (set)ISBN 1 870004 61 2 (vol 4)

©The Steel Construction Institute 1991

The Steel Construcon Institute Offices also at:SilwoodPark

Ascot Unit820Berkshire SL5 7QN Birchwood Boulevard B-3040 HuldenbergTelephone: 0344 23345 Birchwood, Wamngton 52 De LimburgSrumIaanFax: 0344 22944 Cheshire WA3 7QZ Belgium



FOREWORD

This volume, one of he series of SC! Steelwork Design Guides to BS 5950, presentsessential design data, not readily available elsewhere, that is useful o steelworkdesigners and fabricators.

A single volume could not possibly contain all he supplementary information that would berequired ocover the full range of structural steelwork design. To assist the reader, alist of the relevant British Standards and other publications have been ncluded whereappropriate. These, together with the addresses ofproduct manufacturers provided in thisguide will enable users to obtain quickly all the information they require. An effort hasbeen made to keep detailed description of he background o the data to aminimum.

This guide has been compiled mainly from various publications ofThe British StandardsInstitution, British Constructional Steelwork Association, Building Research Establishment,British Steel General Steels, and from technical literature supplied by manufacturers; thesource of ome of he material included is not clearly identifiable. Acknowledgements havebeen ncluded, where possible, in the relevant Sections. Details of advisory bodies arecontained in Section 20 of this publication.

Extracts from British Standards are reproduced with he permission of he British StandardsInstitution. Copies of he Standards can be obtained by post from BSI Sales, Linford Wood,Milton Keynes, MK14 6LE; telephone: 0908 221166; Fax: 0908 322484.

The publication has been made possible by sponsorship from British Steels General Steels,which is gratefully acknowledged.

The publication was edited by Mr D M Porter of he University of Wales College ofCardiffand Mr A S Malik of he Steel Construction Institute.



CONTE NTS

Page

1. LOADS 1-1

1.1 Dead loads 1-11.2 Other design data 1-5

1.3 Imposed and wind oads on buildings 1-71.4 Member capacities 1-7

1.5 References 1-8

2. WELDABLESTEELS 2-12.1 Performance requirements ofstructural steels 2-22.2 Mechanical properties 2-32.3 Chemical properties 2-32.4 Rolling olerances 2-102.5 References 2-17

3. COLD FORMED STEEL PRODUCTS 3-13.1 Manufacturers of roof and wall external and internal

cladding 3-1

3.2 Manufacturers of roof purlins and wall sheeting rails 3-23.3 Manufacturers of roof decking 3-33.4 Manufacturers of lintels 3-33.5 Manufacturers ofprofiled decking forcomposite floors 3-53.6 References 3-5

4. COMPOSITE CONSTRUCTION 4-14.1 Composite beams 4-1

4.2 Profiled steel decking 4-14.3 Shear connectors 4-24.4 Welded steel fabric - BS 4483: 1985 4-54.5 References 4-6

5. STEEL SLAB BASES AND HOLDING DOWN SYSTEMS 5-15.1 Design of slab column bases 5-15.2 Concentric oad capacity of slab bases foruniversal columns 5-35.3 Holding down systems 5-35.4 Drawings 535.5 References 57

III



Page

6. BUILDING VIBRATIONS 6-1

6.1 Introduction 6-1

6.2 Vibration ofbuildings 6-1

6.3 Vibration of floors 6-26.4 Human reaction 6-2

6.5 References 6-3

7. EXPANSION JOINTS 7-1

7.1 Background 7-1

7.2 Basics 7-1

7.3 Practical factors - industrial buildings 7-37.4 Practical actors - commercial buildings 7-47.5 Cladding and partitions 7-5

7.6 Detailing ofexpansion joints 7-57.7 Recommendations 7-67.8 Summary 7-87.9 References 79

8. DEFLECTION LIMITATIONS OF PITCHED ROOF STEELPORTAL FRAMES 8-1

8.1 British Standard recommendations 8-1

8.2 Types of cladding 8-18.3 Deflections ofportal frames 8-28.4 Behaviour ofsheeted buildings 8-3

8.5 Behaviour ofbuildingswith external walls 8-3

8.6 Analysis at the serviceability limitstate 8-4

8.7 Building with overhead crane gantries 8-5

8.8 Ponding 8-6

8.9Visual

appearance8-6

8.10 Indicative values 8-6

8.11 References 8-9

9. ELECTRIC OVERHEAD TRAVELLING CRANES AND DESIGNOF GANTRY GIRDERS 9-1

9.1 Crane classification 9-1

9.2 Design ofcrane gantry girders 9-1

9.3 Design and detailing of crane rail track 9-119.4 Gantry girder end stops 9-12

9.5 References 9-12

10. FASTENERS 10-1

10.1 Mechanical properties and dimensions 10-1

10.2 Strength grade classification 10-1

10.3 Protective coatings 10-10

iv



Page

10.4 Minimum length ofbolts 10-1010.5 Designation of bolts 10-1010.6 References 10-10

11. WELDINGPROCESSES ANDCONSUMABLES 11-111.1 Basic requirements 11-111.2 Manual metal-arc (MMA) welding 11-111.3 Submerged arc (SA) welding 11-211.4 Gas metal arc welding (GMA) 11-311.5 Gas shielded flux-cored arc welding (FCAW) 11-311.6 Consumable guide electroslag welding (ESW) 11-411.7 Stud welding 11-5

11.8 Manual metal arc (MMA) electrodes 11-711.9 BS 7084: 1988 carbon and carbon manganese steel tubularcored weldingelectrodes 11-12

11.10 BS 4165: 1984 electrode wires and fluxes for the submergedarc wedling of carbon steel and medium-tensile steel 11-14

11.11 References 11-15

12. STEEL STAIRWAYS, LADDERSANDHANDRAILING 12-1

12.1 Stairways and ladders 12-112.2 Handrailing 12-112.3 Detailed design 12-112.4 Listof manufacturers 12-312.5 References 12-3

13. CURVED SECTIONS 13-113.1 General 13-1

13.2 Minimum bend radii 13-113.3 Material properties ofcurved members 13-113.4 Bending of hollow sections for curved structures 13-313.5 Accuracy of bending 13-513.6 References 13-5

14. STAINLESSSTEELIN BUILDING 14-114.1 Introduction 14-1

14.2 Stainless steel types 14-114.3 Corrosion 14-114.4 Staining 14-214.5 Surface finish 14-214.6 Fabrication 14-214.7 Applications and design considerations 14-214.8 Material grades 14-414.9 References 14-5

V



Page

15. FIRE PROTECTION OF STRUCTURAL STEELWORK 15-115.1 Section factors 15-115.2 Forms of protection 15-115.3 Performance ofproprietary fire protective materials 15-215.4 Amount ofprotection 15-315.5 Calculation of Hp/Avalues 15-315.6 Half-hour fire resistant steel structures, free-standing block-tilled

columns and stanchions 15-1115.7 Fire resistant ofcomposite floors with steel decking 15-1415.8 Concrete filled hollow section columns 15-1615.9 Water cooled structures 15-1615.10 References 15-16

16. BRITISH STEEL - SPECIALISED PRODUCTS 16-116.1 Durbar floor plates 16-116.2 Bridge and crane rails 16-516.3 Bulb lats 16-716.4 Round and square bars 16-1016.5 References 16-10

17. BRITISH STEEL - PLATE PRODUCTS 17-117.1 Plate products - range ot sizes 17-117.2 References 17-8

18. TRANSPORTATION, FABRICATION AND ERECTION OFSTEELWORK 18-1

18.1 Transportation ofsteelwork 18-118.2 Fabrication tolerances 18-318.3 Accuracy of erected steelwork 18-318.4 References 18-3

19. BRITISH STANDARDS 19-i

20. ADVISORY BODIES 20-1

APPENDIX- Metric conversion tables

A-i

vi



1. LOADS

This Section contains essential design data on dead loads, other design data, mposed oadsand wind oads for nonnal design situations.

1.1 Dead loadsInformation on dead loads is given below.

Table 1.1 contains general data on he unit weight of bulk materials. More detailedinformation sgiven in BS 648(1). However, or final design puiposes, referenceshould be made to the manufacturers' publications.

Table 1.2 provides nformation on packaged materials; Table 1.3 pertains to buildingmaterials; and Table 1.4 to floors, walls and partitions.

Table 1.1 Bulk materials: approximate unit weights

Material kN/m3 Material kN/m3

Ashes, coal 7.05 Brass, rolled 83.84Asphatt, paving 22.64 Bronze 82.27Ballast, brick, gravel 17.54 Copper, cast

Copper, rolled86.3487.60

Cement, portland oose 14.11 Iron,cast 70.66Cement, mortar 1646 Iron,wrought 75.36Clay, damp, plastic 17.54 Lead, cast 111.13

Concrete, breeze 15.09 Lead, sheet 111.42Concrete, brick 18.82 Nickel, monel metal 87.27Concrete, stone 22.64 Steel, cast 77.22Earth, dry, loose 11.30 Steel, rolled 77.22Earth, moist, packed 15.09 Tin,cast 71.44Earth, dry, rammed 17.54 Tin, rolled 72.52Glass, plate 27.34 Zinc 68.60Glass, sheet 24.50Gravel 18.82 NATURAL STONELimemortar 16.17 Slate

Flint28.2225.90

MASONRY Granite 26.70Artificialstone 22.60 Limestone 25.13Freestone, dressed 23.52 Macadam 23.57Freestone, rubble 21.95 Marble 25.92Granite dressed 25.92 Sandstone 23.57Granite, rubble 24.30

METALS Pitch 10.98Aluminium , cast 27.15 Plaster 15.09Brass, cast 82.71 Plaster of Paris, set 12.54

Continued

1—1



Table 1.1 (Continued)


REINFORCED CONCRETE TIMBER2% steel 23.55 Softwoods:3% steel 24.55

Sand, dry 15.68

Pine, Spruce,Douglas FirRedwood

4.725.50

Sand, wet 19.60Pitchpine

6.60

Steel 77.22 Hardwoods:Teak, Oak 7.07

Tar 10.05Terra-cotta 17.60

For urther nformation refer to BS 648(1): Weights ofbuilding materials.

Table 1.2 Pac*aged materials: approximate nitweights


CEREALS ETC.Barley, in bags 5.65 Lime, n barrels 7.85Barley, in bulk 6.28 Oils, n bulk 8.79Flour, in bags 7.07 Oils, n barrels 5.65Hay, in bales, compressed 3.77 Oils, n drums 7.07Hay, not compressed 2.20 Paper, printing 6.28Oats, n bags 4.24 Paper, writing 9.42Oats, n bulk 5.02 Petrol 6.59Potatoes, piled 7.07 Plaster, in barrels 8.32Straw, n bales compressed 2.98 Potash 32.14Wheat, n bags 6.12 Red Lead, dry 20.72

Wheat, n bulk 7.07 Rosin, in barrels 7.54Rubber 9.42MISCELLANEOUS Saltpetre 10.52Bleach, in barrels 5.02 Screw nails, in packages 15.70Cement, in bags 13.19 Soda ash, in barrels 9.73Cement, in barrels 11.46 Soda, caustic, in drums 13.82Clay, china, kaolin 21.67 Snow, freshly allen 0.94Clay, potters, dry 18.84 Snow, wet, compact 3.14Coal, oose 8.79 Starch, in barrels 3.93Coke, oose 4.71 Sulphuric acid 9.42Crockery, in crates 6.28 Tin, sheet, n boxes 43.65Glass. n crates 9.42 Water, resh 9.81

Glycerine, in cases 8.16 Water, sea 10.05Ironmongery, in packages 8.79 Whitelead, dry 13.50Leather, in bundles 2.51 White lead paste, in drums 27.32Leather, hides compressed 3.61 Wire, n coils 11.62

1-2



Table 1.3 Buildingmaterials: approximate unit weights

Material kN/m2

ALUMINIUM ROOF SHEETING 1.2 mm ThICK 0.04

ASBESTOS CEMENTSHEETINGCorrugated 6.3 mm thickas aid 0.16Flat 6.3 mm hick as aid 0.11

ASPHALTRoofing, 2 layers, 19 mm thick 0.41

25 mm thick 0.58Bitumen, built up elt oofing3 ayers including chippings 0.29

BLOKWORK excludes weightofmortar)Concrete, solid,per 25 mm 0.54Concrete, hollow, per 25 mm 0.34Lightweight, solid,per 25 mm 0.32

BRICKWORK(excludes weight

ofmortar)Clay, solid,per 25 mm hick 0.45

Lowdensity 0.49Medium density 0.54Highdensity 0.58Clay, perforated, per 25 mm thickLowdensity 25% voids 0.38

15% voids 0.42Medium density 25% voids 0.40

15% voids 0.46High density 25% voids 0.44

15% voids 0.48

BOARDSCork, compressed, per 25 mm hick 0.07Fibre insulating, per 25 mm hick 0.07Laminated blockboard, per 25 mm hick 0.11Plywood, 12.7 mm thick 0.09

GLASSClear loat, 4 mm 0.09

6mm 0.14

GLASS FIBREThermal insulation, per 25 mm hick 0.005

Acoustic insulation, per 25 mm thick 0.01

GLAZING, PATENT (6.3 mm Glass)Lead covered bars at 610 mm centres 0.29Aluminium alloy bars at 610 mm centres 0.19

LEAD,SHEET PER 3 mm ThICK 0.34

PLASTERGypsum 12.5 mm thick 0.22

PLASTERBOARD GYPSUM9.5 mm hick 0.0812.5 mm hick 0.1119.0 mm hick 0.17

ROOF BOARDINGSoftwood rough sawn 19 mm hick 0.10Softwood rough sawn 25 mm hick 0.12Softwood rough sawn 32mm thick 0.14

Continued

1-3



Table 1.3 (Continued)

Matenal kN/m2

RENDERINGPortland cement: sand 1:3 mix, 12.5mm thick 0.29

SCREEDINGPortland cement: sand 1:3 mix, 12.5mm thick 0.29Concrete, per 25 mm thick 0.58Lightweight, per 25 mm thick 0.32

STEELROOF SHEETING0.70 mm thick (as laid) 0.071.2Ommthick(aslaid) 0.12

flUNG, ROOFClay or concrete, plain, aid to 100 mm gauge 0.62-0.70Concrete, interlocking, single lamp 0.48-0.55

hUNG, FLOORAsphalt 3 mm hick 0.06Clay 12.5 mm thick 0.27Cork, compressed 6.5 mm hick 0.025PVC, lexible2.0 mm thick 0.035Concrete 16 mm thick 0.38

WOODWOOL SLABS, per 25 mm hick 0.15

Table 1.4 Floors wailsandpartitions: approximate unit weights

(a) Reinforced concrete floors

Thickness Dense concrete Lightweight concretemm kN/m2 kN/m2

100 2.35 1.76125 2.94 2.20150 3.53 2.64175 4.11 3.08200 4.70 3.52225 5.30 3.96250 5.88

4.40Dense concrete is assumed o have natural aggregates and 2%reinforcement witha mass of2400 kg/m3. Lightweight concreteis assumed to have a mass of1800 g/m3.

(b) Steel loors

Durbar non-slip Open steel looring

Thicknesson plain

mm kN/m2

kN/m2Thickness

mm Light Heavy4.5 0.376.0 0.498.0 0.64

10.0 0.8012.5 0.99

20 0.29 0.3825 0.38 0.4630 0.44 0.5640 0.60 0.7450 0.74 0.90

Open steel loors are available from various manufacturers toparticularpatterns and strengths. The above average igures areforguidance in preliminaiy design. Manufacturers' data shouldalways be used or inal design.

Continued



TabI. 1.4 (Continued)

(C) Timber floors (solid imber, oist sizes, mm), unitweightkN/m2

Joistcentres Decking

Joist sizes

75x50 1 00x50 150x50 200x50 225x50 275x50

400mm

600 mm

19 mm Softwood

19 mm Chipboard22 mm Chipboard

19 mm Softwood19 mm Chipboard22 mm Chipboard

0.16 0.18 0.21 0.25 0.27 0.30

0.19 0.21 0.24 0.28 0.30 0.330.21 0.23 0.26 0.30 0.32 0.35

0.14 0.16 0.18 0.20 0.21 0.240.17 0.19 0.21 0.23 0.24 0.270.19 0.21 0.23 0.25 0.26 0.29

The solid imber oists are based on a density of5.5 kN/m3.

(d) Wall: approximate unitweights ordesign

kN/m2Construction

Brick Block Brick+ Block

102.5 mm hickPlain 2.17 1.37Plastered one side 2.39 1.59Plastered both sides 2.61 1.81

215mm thickPlain 4.59 2.99Plastered one side 4.81 3.21Plastered both sides 5.03 3.43

3.794.014.23

255 mm Cavity wallPlain 4.34 2.74Plastered one side 4.56 2.96Plastered both sides 4.78 3.18

3.543.763.98

Assumed unit weight ofbrickwork 21.2 kN/m3Assumed unit weight ofblockwork 13.3 kN/m3

(a) Partitions

Timber partition (12.5 mm plasterboard each side)Studding with lath and plaster

0.25 kN/m2

0.76 kN/m2

Forspecific ypes and makes ofwallsand partitions, reference should bemade to he manufacturers' ublications.

1.2 Other design dataDetails about the angle of epose ofbulk materials, coefficient ofactive pressure orcohesionless materials and coefficients of inear thennal expansion ofbuilding materialsare given below.

1.2.1 Angle of repose of bulk materialsFor preliminary design, he angle of repose values given inTable 1.5 could be used. Infinal design amore accurate value of the actual material should always be obtained andused.

1-5



TabI. 1.5 Angle ofTOOS9

Material Unitweight Angle ofrepose, 0kN/m3

Ashes 6.3 - 7.9 400Cement 14.1 20°Cement (clinker) 14.1 30°Chalk

(in lumps)11.0 - 12.6 35° - 450

Clay (in lumps) 11.0 30°Clay (dry) 18.8 - 22.0 30°Clay (moist) 20.4 - 25.1 45°Clay (wet) 20.4 - 25.1 15°Clinker 10.2 40°Coal (in umps) 8.8 35°Coke 5.5 30°Copper ore 25.1 - 28.3 350Crushed brick 12.6 - 15.7 35° - 40°Crushed stone 17.3 - 20.4 35° - 40°Granite 17.3 - 31.0 35° 40°Gavel clean) 14.1 - 17.3 35° - 40°Gravel (withsand) 15.7 - 17.3 25° - 30°Haematite iron ore 36.1 350Lead ore 50.2 35°Limestones 12.6 - 18.8 35° - 45°Magnetite ironore 39.3 350Manganese ore 25.1 - 28.3 350Mud 16.5 - 18.8 0°Rubblestone 17.3 - 18.8 45°Salt 9.4 30°Sand (dry) 15.7 - 18.8 30° - 350Sand (moist) 18.1 - 19.6 35°Sand (wet) 18.1 - 20.4 25°Sandstones 12.6 - 18.8 350 - 450Shale 14.1 - 18.8 30° - 35°Shingle 14.1 17.3 30° - 40°Slag 14.1 35°Vegetable earth (dry) 14.1 - 15.7 30°Vegetable earth (moist) 15.7 - 17.3 45° - 50°Vegetable earth (wet) 17.3 - 18.8 15°Zincore 25.1 . 28.3 35°

1.2.2 Coefficient of active pressure

The coefficient of active pressure forcohesionless materials s given in Table 1.6

Table 1.6 Values ofKa coefficient ofactive pressure) forcohesionless materials

Wall Ka orvalues ofangle ofrepose 0)friction,

25° 30° 35° 40° 45°

0° 0.41 0.33 0.27 0.22 0.1710° 0.37 0.31 0.25 0.20 0.16

20° 0.34 0.28 0.23 0.19 0.1530° — 0.26 0.21 0.17 0.14

This able may be used to determine the horizontal pressure, PainkN/m2, exerted bystored materiaL

— unit weightxdepth ofstored material xKa

The effect ofwall riction Iion active pressures is small and is usually gnored.The above values ofKa assume verticalwalls with horizontal ground surface.

The above data should notbe used n the design calculations for silos, bins, bunkers and

hoppers.

1-6



1.2.3 CoefficIents of linear thermal expansionThe coefficients of inear thennal expansion for some common building materials sgiven in Table 1.7.

Table 1.7 Coefficients of inear thermal expansion forsome common buildingmaterials

Material (per deg. C. x 104)

Aluminium 0.24Brass 0.19Copper 0.17Glass (fIat) 0.08Iron (cast) 0.10 - 0.13Iron (wrought) 0.12Mild Steel 0.12Lead 0.29Wood-hard or soft (par. to grain) 0.04 - 0.06

(across grain) 0.30 - 0.70Zinc -highpurity 0.4Die-cast alloy to BS 1004 0.27Zn-Tialloysheeting 0.21

1.3 Imposed and wind loads on buildings1.3.1 Imposed loadsThe imposed oads which have to be considered when designing floors, ceilings, stairwaysand walkways for the various categories ofbuildings such as domestic, commercial ndindustrial are given in BS 6399: Part 1: 1984(1). Given also n the above standard

are the imposed loads for designing vehicle barriers, balustrades etc.

Also included are the design oads for crane gantry girders and for dynamic effects otherthan that of wind oads.

1.3.2 Wind loads

Atpresent he code ofpractice forwind loading s CP3, Chapter V, Part 2:1972(1) butthis standard will be replaced byBS 6399: Part 2.

1.3.3Roof and

snowioads

Minimum imposed oads and snow loads on roofs are given in BS 6399: Part 3: 1988(1):

Section 1 Minimum imposed roof oadsSection 2 Snow oads

1.4 Member capacities

Steelwork design guide to BS 5950: Part 1: 1985 Volume J(2) published by the Steel

Construction Institute, provides section properties and member capacities ofall steel sectionsmanufactured in the United Kingdom. This guide contains Member Capacity Tables classifiedas given below:

I and H section strutsHollow section strutsChannel trutsAngle strutsAngle iesI and H sections subject o bending

1-7



I and H sections: bearing and bucklingHollow sections subject to bendingHollow sections: bearing and bucklingChannels subject to bendingChannels: bearing and bucklingI and H sections: axial load and bendingHollow sections: axial load and bendingChannels: axial oad and bending

Bolt capacitiesWeld capacitiesFloor plates

1.5 References1. BRiTISH STANDARDS INSTITUTION

(see Section 19)

2. THE STEEL CONSTRUCTION INSTITUTESteelwork design guide to BS 5950: Part 1: 1985, Volume 1 - Section properties andmember capacities, 2nd EditionSC!, Ascot, 1987

1-8



2. WELDABLE STEELS

This Section covers chemical and mechanical properties ofweldable structural steels toBS 4360: 1990(1), BS EN 10025: 1990(1) (grades Fe 360, Fe 430 and Fe 510) androffing tolerances for plates, bars and all structural sections.

In elation o the EC Commission's Construction Products Directive and the materialrequirements of hedraft European Standard for Design ofSteel Structures (Eurocode 3),the European Committee for Iron and Steel Standardisation ispreparing a series ofEuropeanStandards for structural steels. EN 10025 is he first n he series o be made availableand was published in he UK by the British Standards Institution during he summer of 1990.The British version of his standard (BS EN 10025(1)), together with BS 4360: )99Q(l)supersede BS 4360: 1986 which is withdrawn. The requirements for those productsand grades notwithin the scope of BS EN 10025 are simultaneously republishedunchanged asBS 4360: 1990(1). The grades ofBS 4360: 1986 superseded by BS EN 10025are:

40 A, B, C, D;43 A, B, C, D and50 A, B, C, D, DD.

Other grades not isted above are incorporated inBS 4360: 1990(1). Table 2.1 gives a comparisonbetween BS 4360: 1986nomenclature and BS EN 10025 nomenclature.

Table 2.1 Comparison ofBS4360:1986 and BSEN 10025 omenclature

(Figures in parentheses refer to the notes ollowing his table)BS EN 10 025 grades BS 4360:1986 grades

Fe310-0(1)(4) -

Fe 360 A(2)Fe36OBFe36OB(FU)Fe36OB(FN)Fe 360 CFe 360 DlFe 360 D2

40A--

40B40C40D40D

Fe 430 A(2)Fe43OBFe43OCFe43001Fe430D2

43A43B43C43D430

Fe 510 A(2)Fe51OBFe51OCFe51001Fe51OD2Fe 510 DD1(3)F. 10 DD2(3)

50A50B50C50D50D5ODD5ODD

Fe 490-2(1 )(4)Fe 90-2(1 )(4)

Fe 90-2(1 (4)

---

(1) There is no equivalent BS4360:1986 grade.(2) The 'A ubgrades only appear nAnnex 0of he UK edition of he European Standard.(3) The Charpy V-notch acceptance criteria forFe 510 DDI/D02are different rom those of

BS4360:1986 grade 5000.(4) These grades are notsuitable foruse as weldable structural steels.

(FU) Rimming steal(FN) Rimming steel notpermitted

2 1



The main differences between BS EN 10025 andBS 4360: 1986 are as follows:

• Different nomenclature for he various grades.

• Omission of certain grade: (e.g. E, EE, F) which are covered separately inBS 4360: 1990.

• The scope of he standard with reference to tensile properties for plates, wide flats and

sections has been increased to 250 mm from 150 mm, 63 mm and 100 mm respectively.• The scope of he standard with reference to impact properties for plates and wide

flats has been ncreased to 250 mm from 100 mm and 50 mm respectively. A limitingthickness of 100 mm has been introduced for sections.

Fuller nformation on the comparison between BS EN 10025 andBS 4360: 1986 isgiven in aninformation rochure entitled BS EN10025 vs BS 4360:1986- Comparisons and Comments (2)

which is available from the British Steel General Steels.

2.1 Performance requirements of structural steelsBS 4360: 1990(1) and BSEN 10025: 1990(') (grades Fe 360, Fe 430 and Fe 510)together specify he requirements for weldable structural steels for general structural andengineering purposes n the form ofhot rolled plates, flats, bars and for the structural sectionscomplying with BS 4: Part (1) and BS4848 Parts 2,4 and 5(1) For hollow sections formedfrom plate and with metal-arc welded seams only the plate material is covered by BS 4360: 1990(1).

BS 5950: Part 2(1) requires that all structural steels shall comply with BS 4360(1) orBS EN 10 025(1) (grades Fe 360, Fe 430 andFe 510) unless otherwise specified by the engineer.

The performance requirements listed in Table 2.2 must be specified for steels not complyingwith BS 4360(1) orBS EN 10025(1) and compliance with hese requirements(Table 2.2) must be detennined by the test procedures ofBS 4360(') (orBS EN 10025(1)).

Where structural steelwork is designed using plastic heory then the steels must begrades 43, 50, 55 and WR5O ofBS4360(1) (or grades Fe 360, Fe 430 and Fe 510 ofBS EN 10 025(1)). For other steels it must be demonstrated that the additional requirements forplastic heory in Table 2.2 have been determined in accordance with the test procedures ofBS 4360(1) (orBS EN 10 025(1)).

Table 2.2 Performance requirements forstructural tee!woik

Performance equirement Specified by Additional requirements forsteel nstructures esigned by the plastic heory

Yield strength Upperyield strength -ReHRm/ReH 1.2

Minimum tensile strength Tensile strength Rm

Notch oughness Minimum average Charpy V-notchimpact est energy at specifiedtemperature (see BS 4360)

None

Ductility Elongation ina specified gaugelength

Stress-strain diagram to have a plateau at

yieldstress extending for at east sixtimes he yield strain.

The elongation on a gauge length of5.651S0 s not to be ess han 15% whereS0 is as given n BS EN 10 002-1:1990(1)

Weidability Maximum carbon equivalent value None

Quality offinished steel BS 4360 and BS EN 10 025 None

2-2



As far as design o BS 5950: Part J(1) is concerned, designers now need to understandall references to "BS 4360 grades" as references to "BS 5950 design grades". Table 2.3 givenbelow isused to translate the "design grades" as used in BS 5950: Part 1 into therelevant grades inBS EN 10025 orBS 4360: 1990 as relevant.

Table 2.3 Appropriate product grades corresponding to 885950 design grades(Figures in parentheses refer to he notes ollowing his able)

Design gradEProduct form

Sections (other hanhollow sections)(1 ,5)

Plates, wide lats,strip (1,5)

Flats, round andsquare bars (1,5)

Hollow sections

43A

43B43B(T)43043D

43DD

43E43EE

Fe 430 A(2)orFe43OBFe 430 BFe 430 B(6)Fe 430 CFe 430 D

43D0 (3)

(4)(4)

Fe 4.30 A(2)orFe43OBFe 430 BFe 4.30 B(6)Fe 430 CFe 430 D

(4)

(4)43 EE (3)

Fe 430 A (2)orFe43OBFe 430 BFe 4.30 B (6)Fe 430 CFe 430 D

(4)

43E (3)(4)

(4)

(4)(4)

430 (3)43D 3)

(4)

(4)43EE (3)

50A

50B50B(T)50050D50D0

50E5OEE

50F

Fe 510 A(2)orFe5lOBFe5IOBFe 510 B(6)Fe51OCFe51ODFe 510 DD

55E 3)(4)

(4)

Fe 510 A(2)orFe5lOBFe51OBFe 510 B (6)Fe51OCFe51ODFe 510 DD

(4)

5OEE (3)

50F (3)

Fe 510 A (2)(5)orFe5lOBFe51OBFe 510 B (6)Fe51OCFe 5100Fe 510 00

50E 3)

(4)

(4)

(4)

(4)(4)

500(3)530(3)

(4)

(4)5OEE 3)

(4)55055EE55F

550 (3)(4)(4)

55C (3)55EE (3)55F (3)

550 (3)55EE (3)(4)

550 (3)55EE 3)55F (3)

WR5OAWR5OBWR5OC

WR5OA (3)WR5OB (3)WR5OC (3)

WR5OA 3)WR5OB (3)WR5OC (3)

WR5OA (3)WR5OB (3)WR500 (3)

WR5OA (3)WR5OB (3)WR500 (3)

(1) Unless shown otherwise, grades n this product orm are supplied in accordance withBS EN 10 025(2) These grades are supplied n accordance with BS EN 10025 Annex 0, Non-conflicting national additions.(3) These grades are supplied n accordance with BS 4360:1990.

(4) Grades in thisproduct formare not ncluded n either BS EN 10025 or BS 4360:1990.(5) Products certifiedas complying withBS4360:1986 having he same grade designation as the BS 5950design grade designation are permitted lternatives.

(6) Fordesign grades 438(T) and 508(T), verification of he mpact properties ofqualityBby testing shallbe specified under Option 7ofBS EN 10 025 at he timeofenquiryand order.

2.2 Mechanical propertiesThe mechanical roperties ofBS 4360(1) steels including weather resistant (WR) gradesate given in Tables 2.4 to 2.9. For the steels within the scope of BS EN 10 025(1),the mechanical properties are given in Tables 2.10 to 2.11.

2.3 ChemIcal propertIesThe chemical properties ofBS 4360 steels ncluding weather esistance WR) gradesare given in he Tables 12, 14, 16, 18,20 and 22, ofBS 4360: 1990(1). The chemicalproperties of steels within the scope of BSEN 10025 are given in Tables 2 and 3 ofBS EN 10025.

2-3



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Table 2.5 Mechanical properties orsections (other han hollowsections) (Asper Table 15 of8$ 4360: 1990)(Figures in parentheses refer to he notes following this able)

Tensile strength,Rm

Minimum yield strength, Re, or thicknesses(in mm)

Minimum elongation, A,on a gauge length of

Minimum CharpyV-notch impacttest value

Grade

Up o andincluding16

Over 16up to and

including40

Over 40up o and

including63

Over63up to and

including100

200 mm 1) 5.651S0 Temp. Energymm.

value

N/mm2(2)340/500

N/mm2260

N/mm2245

N/mm2240

N/mm2225

%22

%25

°C-30

J27 400D

430/580 275 265 255 245 20 22 -30 27 43DD

490/640(3) 355 345 340 325 18 20 -40 27 50E

Up to andincluding16

Over 16up to andincluding25

Over 25up o andincluding40

500/700 450 430 415 - 17 19 0 27(4) 55C

(1) Up to and ncluding 9mm hick, 16% forgrades 40 and 43 and 15% or grades 50 and 55.(2) 1 N/mm2 - IMPa(3) Minimum tensile strength 480 N/mm2 formaterial over 16mm thick up o and ncluding 100 mm thick.(4) To maximum thickness of19 mm.

Table 2.6 Mechanical properties or lats and round and square bars (As per Table 17ofBS 4360: 1990)(Figures in parentheses refer to he notes ollowing his able)

Tensile strength,

Rm

Minimum yield strength, Re, or thicknesses

(in mm)

Minimum

elongation,A,on a gaugelength of5.651S0

Minimum Charpy

V-notch impacttest value

Grade

Up to andincluding16




Temp. Energymm.value

N/mm2(1)340/500

N/mm2260

N/mm2245

N/mm2240

N/mm2225

%25

°C-40

J27(2) 40E

430/580 275 265 255 245 22 .40 27(2) 43E

490/640(3) 355 345 340 325 20 -40 27(2) 50E

Up o andincluding16




550/700550/700

450450

430430

415415

-400

1919

0-50

27(4)27(4)

55C55EE

(1) IN/mm2_1MPa.(2) To a maximum thickness of75mm.(3) Minimum tensile strength 480 N/mm2 ormaterial over 16 mm thick up to and including 100mm hick.(4) To maximum hickness of 19 mm.

2-5



Table 2.7 Mechanical roperties orhollowsections (1) (As per Table 19 ofBS 4360: 1990)(Figures in parentheses refer to he notes ollowing this table)

Tensile strength,Rm

Minimum yield strength, A9,for hicknesses (in mm)Minimumelongation,A,on agauge engthof5.65IS0

Minimum Charpy V-notchimpact est value

Grade

Temp. Energymm.value

Thicknessmax.

Up o andincluding16

Over 16uptoandincluding

40(2)N/mm2(3)430/580430/580430/580

N/mm2275275275

N/mm2265265265

%222222

°C0(4)-20-50

J272727

mm404040

43C43043EE

490/640490/640490/640

355355355

345345345

212121

0-20-50

272727

404040

50050D5OEE

Uptoandincluding

16

Overl6up to and

including25 (2)

550/700550/700550/700

450450450

430430430

191919

0-50-60

272727

252525

55C55EE55F

(1) Fordetails of lattening test see Clause 28, ofBS 4360.(2) Onlycircular hollowsections are available in thicknesses over 16 mm.(3) 1 N/mm2 =1 MPa.(4) Verification of he specified mpact value obe carried outonly when option specified n BS 4360 s

invokedby he purchaser.

Table 28 Mechanical properties orplates, strip, wide flats, flats, sections (other han hollow sections) and oundand square bars: weather esistant grades As per Table 21 ofBS 4360:1990)(Figures in parentheses refer to he notes ollowing his able)

Minimumtensilestrength,Rm

Minimum yield strength, A9, for hicknesses(in mm)

Minimumelongation, A,ona gauge length of

Minimum Charpy V-notchimpact test value

Grade

Up o andincluding12


25


40


50

200 mm(1)

5.65IS0 Temp. Energymm.value

Thicknessmax.

N/mm2(2)480

480

480

N/mm2345

345

345

N/mm2325

345

345

N/mm2325

345

345

N/mm2-

340

340(4)

%19

19

19

%21

21

21

O()0

0

-15

J27

27

27

mm12(3)

50

50

WR5OA

WR5OB

WR5OC

(1) Minimum elongation of 17% formaterialunder 9 mm.(2) 1 N/mm2 — 1 MPa.(3) For ound and square bars, maximum thickness is 25 mm.(4) Up o and ncluding 63 mm.

2-6



Table 2.9 Mechanical roperties or hollow sections: weather esistant grades 1) (Asper Table 23ofBS4360: 1990)(Figures inparentheses efer to he notes ollowing his able)

Tensilestrength,Rm

Minimum yield strength, Re, forthicknesses (in mm)

Minimumelongation, A,onagaugelength of5.65'S0

Minimum Charpy V-notchimpact est value

Grade

Temp. Energymm.

Thicknessmax.

Up to andinduding

12

Over 12up o and

including25 (2)

Over25up to and

including40

N/mm2(3)480

480

480

N/mm2345

345

345

N/mm2325

345

345

N/mm2325

345

345

%21

21

21

°C0

0

-15

J27

27

27

mm12

40

40

WR5OA

WR5OB

WR5OC

(1) Fordetails of lattening test see Clause 28ofBS 4360.(2) Onlycircular hollowsections are available in hicknesses over 16mm.(3) 1 N/mm2 — 1 MPa.

2-7



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2 3 3

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Table 2.10 Mechanciai roperties or latand ong products continued)(Figures inparentheses efer to he notes ollowing this able)

Designation Type ofdeoxi-dation(6)

Sub-group(4)

Positionof estpieces(1)

Minimum percentage elongation (1)

L.—80 mmNbminal thickness in mm— — — — —

> 1 > 1.5 >2 >2.51 <3

L0=5.651S0Nbminal thickness in mm— — — — —

3 >40 > 63 > 100> 150

NewaccordingEN1O027-1(2)

AccordingEU 25-72

Fe 310-0 (3) opt. BS 1

t10

8119

1210

1311

1412

1816

-- -- -- --

Fe36OB(3)Fe 360 B 3)

Fo36OBFe36OCFe36OD1Fe 60 D2

opt.FUFNFNFFFF

BSBSBSOSOSOS

1

t

17

15

18

16

19

17

20

18

21

19

26

24

25

23

24

22

22

22

21

21

Fe43OBFe43OCFe43OD1

Fe430D2

FNFNFF

FF

BSOSOS

OS

1

t

14

12

15

13

16

14

17

15

18

16

22

20

21

19

20

18

18

18

17

17

Fe51OBFe51OCFe51001Fe51002Fe51ODD1Fe51ODD2

FNFNFFFFFFFF

BSOSOSOSOSOS

1

t

14

12

15

13

16

14

17

15

18

16

22

20

21

19

20

18

18

18

17

17

Fe 90-2 (5) FN BS 1

t

1210

1311

1412

1513

1614

2018

1917

1816

1615

1514

Fe590-2(5) FN BS 1

t

8

6

9

7

10

8

11

9

12

10

16

14

15

13

14

12

12

11

11

10

Fe 90-2 (5) FN BS 1

t

43

54

65

76

87

11

1010

998

87

76

(1) The values in he table apply to ongitudinal est peices (1) for he tensile test. Forplate, stripand wide flats with widths 600mm transverse est pieces (t) are applicable.

(2) At he moment ofpublicationof he European Standard, the transformation ofEURONORM 27(1974) nto aEuropean standard EN 10 027-1) is notcomplete and may be subject ochanges see BS EN 10 025).

(3) Only available innominal hickness 25mm.(4) BS base steel; QS =qualitysteeL(5) These steels are normally not used forchannels, angles and sections.(6) Methodat he manufacturer's option: FU = rimming steel; FN= rimming steel notpermitted; FF—fully

killedsteelcontaining nitrogen binding

elements in amount sufficient o bind the availablenitrogen.

2-9



Table 2.11 Mechanical roperties - impactstrength KVongitudinal) for lat and ong products (1)(Asper Table 5of88EN 10 025: 1990) (Figures inparentheses refer to he notes ollowing his able)

Designation Type ofdeoxi-

Sub -group(3)

Temperature

°C

Mm. energy J)Nominal thicknessin mmew

according

EN 10 027-1(2)

According

tT25-72

dation(7)

> 10(4)150

>150(4)250

Fe 310-0 (5) opt. BS - - -

Fe 360 B(5)(6)Fe 360 B(5)(6)Fe 360 B(6)Fe36OCFe36OD1Fe 360 D2

opt.FUFNFNFFFF

BSBSBSOSOSOS

2020200

-20-20

272727272727

-•23232323

Fe 430 B(6)Fe430CFe 430 DlFe 430 D2

FNFNFFFF

BSOSOSOS

200

-20-20

27272727

23232323

Fe51OB(6)Fe51OCFe 510 DlFe51OD2Fe 510 DD1Fe 510 DD2

FNFNFFFFFEFF

BSOSOSOSOSOS

200

-20-20-20-20

272727274040

232323233333

Fe 490-2 EN BS - - -

Fe 590-2 FN BS - - -

Fe 690-2 FN BS - - -

(1) Forsubs ze test pieces Figure 1 inBS EN 10025 applies.(2) At he moment ofpublicationof he European Standard the transformation ofEURONORM 27

(1974) into a European standard EN 10027-1) s not complete and may be subject ochanges (see BEEN 10 025).

(3) BS base steel; QS =qualitysteeL(4) Forsections with a nominal hickness> 100 mm he values shall be agreed. Option24

(5eeBSEN 10025, Clause 11).(5) Onlyavailable in nominal hickness 25mm.(6) The impactproperties ofqualityBproducts are verified only when specified at he

timeof he enquiry and order. Option7 see BSEN 10025, Clause 11).(7) Methodat he manufacturer's option: FU— rimmingsteel; FN — rimmingsteel not

permitted; FF—

fullykilledsteel

ontaining nitrogen bindingelements in amount

sufficient to bind he available nitrogen.

2.4 Rolling tolerancesBS 5950: Part 2(') requires hat all plates, bars, flats etc., and hot rolled sections mustcomply with the rolling olerances specified inBS 4360, BS4 and BS 4848(1) asappropriate. These olerances are set out in the sub-sections which follow.

2.4.1 RoIling tolerances for plates, strip, wide flats, rounds and square bars

(a) Plates and sthp

The dimensional and shape olerances for plates and strip produced on continuous mills shall comply withBS 1449: Part (1)• Tolerances for plates produced on non-continuous mills shallcomply with BS 4360(1) Clauses 14.2 to 14.6. The length olerance on ordered lengthshall comply with Table 2 ofBS 4360(1) and the width olerance on ordered widthwith Tables 3 (BS4360); thickness tolerance shall comply with Table 4 (BS 4360) andflatness olerance with Table 5 (BS 4360).

2-10



The specific olerance equirement for edge camber is given in Clause 14.5 ofBS 4360(').

(b) Wide flats

For wide flats (widths of 150 mm and above) the tolerances shall comply with BS 4360Clauses 15.1 to 15.5. The length olerances on ordered ength for wide flats shall be -0, +50 mm.

The width olerances on ordered width for wide flats shall be ±2% ofordered width butshall not exceed ±5 mm.

The thickness tolerances on ordered hickness forwide flats are given inTable 6 ofBS 4360(1).

The edge camber olerance shall be anominal straightness edge camber not exceeding 0.25%of he length of he wide flat (see Clause 15.4 ofBS 4360(1)).

The tolerances of quareness ofends, angular accuracy and flatness shall comply with BS 4360(1)Clauses 15.5, 15.6 and 15.7 respectively. For flats ofwidths of 0-150 mm, the width toleranceson ordered width shall comply with BS 4360(1) Table 9 and thickness tolerancesonordered hickness with Table 10.

(c) Round and square bars

For round and square bars, the size tolerances on ordered size shall comply with BS 4360(')Clauses 17.1 to 17.2 and Table 11.

The length olerances on ordered ength for round and square bars shall be -0, +600 mm.

2.4.2 RoIling tolerances for hot roiled structural steel sectionsHot rolledsections ollowing BS 4: Part 1: 1980(1), (viz beams, columns, joists,channels and tees) are covered below. A hot olled section is designateJ by the serialsize (nominal size) in millimetres and the mass per unit length in kilograms per metre;this form ofdesignation hall be used in any enquiry and order.

(a) Mass and length olerances

Mass: If he order does not state that the actual mass per unit length isaminimum, therolling olerance shall be ±2.5% of he actual mass per unit length.

If he order states that the actual mass perunit ength is a minimum, the rollingtolerance 5%) shall be wholly over the actual mass per unit ength.

Length: Sections ordered as "specified" or as "exact" lengths shall be supplied as follows:

(i) "Specified" lengths; when a section is o be cut to a specified length, it shall be cutto within ±25 mm of that ength. When aminimum ength is specified it shall be cut towithin +50, -0mm of hatminimum length.

(ii) "Exact" length; when a section is to be Cut tø an exact length, it shall be cold sawn

to within ±3 mm of hat ength.

(b) Dimensional rolling olerances foruniversal beams and columns

(i) Cross-sectionThe variations rom the specified dimensions and the correct cross-section shall notexceed hose shown nFigure 2.1 and Tables 2.12 and 2.13.

(ii) StraightnessThe variation from straightness shall not exceed hose tolerances given in Table 2.14.

2-11



(iii) The variations rom the nominal thickness ofweb and flange shall not exceed hetolerances given inTable 2.12(c).

(c) Tolerances on specified depth of oists and channels

The tolerances on specified depth of oists and channels are given inTable 2.15.

(d) Cambering ofuniversal beams from the mill

Camber will approximate to a simple regular curve nearly he full length of he beam, andis customarily specified by the ordinate at the mid-length of he beam to be curved.Ordinates atother points, or reverse orother compound curves are not consideredpracticable.

Small amounts ofcamber may not be permanent because release of he stresses put nto thebeam during he cambering operation may subsequently cause the camber o be ost.

It will be appreciated thatwith such awide range of ections available, with each sizeand weight having different

camberingcharacteristics, it is not feasible

ostate

preciseamounts or limitations ofcamber.

Table 2.12 Tolerances on dimensions and cross-section for universal eams and columns(Asper Table 1 ofBS 4: Pail 1: 1980)

(a) Tolerances on depth and off-centre ofweb foruniversal eams and columns

Serial sizedepth

Tolerances ondepth 0

Tolerances oncross-section

Off-centreofwebe, max

Maximum depthat any crosssection C

Uptoandincluding305 mm

Over 305 mm

mm

±3

± 3

mm

3.0

5.0

mm

D+5.0

D+6.5

2-12

C

Figure 2.1 Key to Tables 2.12 and 2.13



(b) Tolerances on flange width oruniversal eams and columns

Serial size width Tolerances onflange width B

mm mm

Upto and including 130 +3-2

Greater han 130 up to andincluding 210 ±3Greater han 210 up to andincluding 235 ±4Greater han 235 +6

-5

(c) Tolerances on thickness for web and lange of universal beams and columns

Thickness Tolerances

Web t Flange Tmm

Upto but excluding 1010 up o but excluding 2020 up to but excluding 3030 up to but excluding 4040 up to but excluding 5050 and over

mm

±0.7±1.0±1.3±1.7±2.2-

mm

±1.0±1.5±2.0±2.5±3.0±4.0

Table 2.13 Tolerances on out-of-squareness of langes oruniversal eamsand columns Asper Table 2 ofBS 4: Part 1:1980)

Serial size width Out-of-squarenessof langes F + F'

mm

Upto and ncluding 102Greater han 102 upto andincluding 203Greater han 203 up o and

including 305Greater han 305

mm

1.5

3.0

5.06.5

Table 2.14 Tolerances on straightness ofuniversal beams and columns(Asper Table 3 ofBS4:Part 1:1980)

Section type Length, L Straightnesstolerance

Over Upto andincluding

Universal beams

Universal columns

m-

9

13.5

m

Alllengths

913.5

-

mm1.04 L

1.04L9.5

1.04 (L-4.5)

2-13



Table 2.15 Tolerances on specified depth ofoistsand channels (As per Table 4ofBS 4: Part 1:1980)

Nominal depth Maximum permissiblevariation fromspecified depthver Up to and

including

-305381

mm

305381432

mm mm

+3.2 -0.8+4.0 -1.6+4.8 -1.6

2.4.3 RollIng tolerances forequal and unequal angles to BS 4848:Part 4:1972 1986)

(a)Mass olerance - individual angle

(I) up to and including 4 mm thick ±5%(ii) over 4 mm thick +5%, -2%.

(b)Dimensional tolerances

The dimensional tolerances for eg length and section hickness and straightness are givenin Tables 2.16, 2.17 and 2.18 respectively.

Table 2.16 Leg ength (Asper Table 1 ofBS 4848:Part 4:1972(1986)

Leg length A Tolerance onleg lengths Aand B

mm

Up to and including 50Over 50 up to and ncluding 100Over 100 up to and ncluding 150Overl5O

mm

±1+3 -1.5+ 4 -2.0+5-3.0

Table 2.17 Section thickness

Section thickness Tolerance

mm mm

Up o and including 5 ±0.50Over 5 up to and ncluding 10Over 10 upto and ncluding 15Over 15

±0.75±1.00±1.20

2-14



Table 2.18 Straightness

Leg Length A

Tolerance

Over ull bar ength Over any part bar length

Deviation qLengthconsidered

Deviationq

mm

Upto andincluding 80Over 80 uptoand ncluding 150Over 150 uptoand ncluding 200Over 200

0.4% L

0.3% L

0.2% L0.1% L

m

1.5

1.5

2.03.0

mm

6.0

4.5

3.03.0

Straightness is measured n the plane ofeach eg, that leg being horizontal.Deviation between ends ofbars not o exceed q above.

Limitsapply o each plane of he angle.

(c) BarlengthL

(i) +100 mm, -0 mm for normal tolerance(ii) ±3 mm for "fine" tolerance .e. when exact ength ordered.

(d) Out of squareness

(i) Angular olerance ±1°

(ii) Linear deviation from squareness not greater han 2.0mm.

2.4.4 RollIng tolerances forhot finished structural hollow sections (SHS)to BS4848: Part 2

(a) Mass

The rolling olerance on mass shall be: ±6% on individual lengths, +6%, -4% on lots of 10tonnes and over.

(b) Length

(i) Mill Lengths; he tolerances for he standard and special mifi lengths are given inTable 2.19 for CHS andTable 2.20 for RHS.

(ii) Exact Lengths; unless otherwise specified exact engths are supplied oa olerance of+6 mm, -0 mm.

(c) Straightness tolerance

Unless otherwise arranged, stnictural hollow sections shall notdeviate from straightnessby more than 0.2% of he total length, as produced, measured at the centre of the ength.

(d) Dimensional tolerances

The dimensional tolerances are as follows:

(i) Circular hollow sectionsOutside diameter. ±0.5 mm or±1% whichever is he greater

2-15



TabI. 2.19 Length ranges and tolerances for circular hollowsection (CHS)

Size mm Welded Seamless Lengthtolerance mm

0.0. Thickness Standard milllengths m

Special milllengths m

Standard milllengths m

21.3&26.9 afi 6.0&6.4 5.4-7.5 +150-0

+150-0

+150-0

+150 -0

+150-0

33.7-48.3 all 6.0,6.4&7.5 5.4-7.5

60.3-114.3 all 6.0,6.4,7.5& 10 5.4-12

139.7-1 68.3 all 7.5,10 &12 6.1 - 14.6

193.7 up o 12.5 7.5,10 & 12 6.1 - 14.6

16.0 8, 10 &12 +300 - 0

219.1 up to 12.5 10 &12 9- 14.8 +300-0

16.0

20.08,106,8,&10

244.5 6.3-168-12.5

10&12 9-14.8 8,10&1210,12&14

+300-0

20.0 6,8&1O273 6.3- 16.0 10 &12 9- 14.8 +300-0

20.025.0

6,8&104,6&8

323.9 6.3- 16.0 10 &12 9- 14.8 +300-020.025.0

6,8&104,6&8

355.6 8.0-16.0 10&12 9-14.8 +300-0

20.025.0

6,8&104,6&8

406.4 10.0-16.0 10&12 9.14.8 +300-0

20.025.032.0

8,10&124,6&82,4&6

457 10.0- 16.0 10 &12 9-14.8 +300-0

20.025.032.040.0

8,10&126,8&104,6&82,4&6

508 10.0- 16.0 10 &12 9 -14.8 +300-0

20&25324050

6,8&104,6&82,4&63,4&5

2-16



Table 2.20 Length anges and tolerances for ectangular hollowsections (RHS)

Size Welded SeamlessLengthtolerancemm

Squaremm

Rectangularmm

Standard milllengths m

Special milllengths m

Standardlengths m

Maximum exactlengths m

20 x20 - 6.4 5.4 -7.5 +150 -0

25x25&30x30 - 6.4&7.550x25 7.5

40 x40 uptolOOxlOOx8

50 x30 upto120x80x8

7.5,10 &12 5.4- 13.7

100 x 100 xlOup to150 x 150 x 12.5

120 x 80 x1Oup to200 x 100 x 12.5

7.5, 10 &12 6.1 -14.6

150x 150 x 16 200x lOOx 6 10-11.2 5.6-11.2 +300-0

l8OxlSOupto400x400x16 25Oxl5Oupto500x300x16 10&12 9-14.8 +300-0

400 x 00 x 20 500 00 x20 8.5-9.0 random

(ii) Rectangular hollow sectionsOutside dimensions of ides: ±0.5 mm or±1% whichever s he greaterSquareness of sides: 90° ± 10Radii ofcorners: outside - between the limits of 0.5t and 2.Ot

inside - between the limits of 0.5t and 1.5t

where, t s he specified thicknessof he section.

Concavity/convexity, X: ±1% of the length of he side D or B. (This toleranceis measured ndependently of he tolerance on outsidedimension.) See Figure 2.2(a).

Angular wist: 2 mm + (0.5 mmper metre) maximum. Twist ismeasured by laying he section, as produced, on ahorizontal surface with the face at one end pressed

flat against he surface and measuring the differencein height, V, above the surface between he twocorners at he opposite end, see Figure 2.2(b).

X

(a)(b)

FIgures 2.2 Tolerance parameters

2.5 References1. BRITISH STANDARD INSTITUTION

(see Section 19)

2. BRITISH STEEL GENERAL STEELSTechnical nformation brochure, BS EN 10 025 vs BS 4360: 1986 - Comparisons and comments

BRITISH STEEL GENERAL STEELS, Motherwell, 1990

2-17



3. COLD FORMED STEEL PRODUCTS

The following categories of cold formed steel products are used extensively in buildings,in association with structural steelwork:

(1)Roof and wall external

cladding(2) Roof and wall internal cladding(3) Roof purlins and wall sheeting ails(4) Roof decking(5) Lintels(6) Composite floor decking

Design of cold formed steel products and the specifications for their material and

workmanship are covered by BS 5950: Parts 5,6 and 7(1)•

The manufacturers isted below should be contacted ordetails of heir product range,

capacity ables, information regarding fixing details and any technical advice needed.Their products generally conform to the requirements ofBS 5950, Parts 5, 6or 7(1)•

3.1 Manufacturers of roof and wall external and internal claddingAtlas Coated Steels Limited2-6 Rock StreetAshton under Lyme Telephone: 061 3432060Lancs 0L7 9AZ Fax: 061 3431542

Ayrshire Metal Products Daventry) LimitedRoyal Oak WayDaventry Telephone: 0327 300990Northants NN1 1 5NR Fax: 0327 300885

British Steel ProfilesNewton Aycliffe WorksAycliffe ndustrial EstateNewton Aycliffe Telephone: 0325 312343Co. Dutham DL5 6AZ Fax: 0325 313358

Conder CladdingShaw StreetHill topWest Bromwich Telephone: 021 556 4211West Midlands B70 OTX Fax: 021 505 1228/502 5385

412 Glasgow RoadClydeBank Telephone: 0419527831Dunbartonshire G81 1PP Fax: 041 952 7720

CorrugatedSheets and Profiles Limited

Ridgacre RoadBlack LakeWest Bmmwich Telephone: 021 553 6771West Midlands B71 1BB Fax: 021 500 6133

3-1



Euroclad (South Wales) LimitedWentloog ndustrial EstateWentloog Telephone: 0222 790722Cardiff CF3 8ER Fax: 0222 793149

European Profiles LimitedLlandybieAmmanford Telephone: 0269 850691Dyfed SA183JG Fax: 0269851081

Grenge Industries LimitedHouston ndustiial EstateLivingston Telephone: 0506 32551West Lothian EH54 5DH Fax: 050634386

Huurral LimitedGreenfleld Business Park Number 2GreenfieldHolywell Telephone: 0352 714545Clywd CH8 7EP Fax: 0352 710760

Kingspan Building Products LimitedNew RoadDudley Telephone: 0384 456501West Midlands DY2 9AZ Fax: 0384 259343

Precision Metal Forming LimitedSwindon RoadCheltenham Telephone: 0242 527511Gloucester GL51 9LS Fax: 0242 518929

Strainit Industries LimitedYaxleyEye Telephone: 037 983 465Suffolk 1P23 SBW Fax: 037 983 659

Ward Building Systems LimitedWidespan WorksSherbumMalton Telephone: 0944 70421North Yorkshire Y017 8PQ Fax: 0944 70512

3.2 Manufacturers of roof purlins and wall sheeting railSAyrshire Metal Products (Daventry) LimitedRoyal Oak Way

Daventry Telephone: 0327 300990Northants NN11 5NR Fax: 0327 300885

Hi-Span LimitedAyton RoadWyinondham Telephone: 0953 603081Norfolk NR18 ORD Fax: 0953607842

3 2



Kingspan Building Products LimitedNew RoadDudley Telephone: 0384 456501West Midlands DY2 9AZ Fax: 0384 259343

Metal Sections LimitedBinningham Road

OldburyWarley Telephone: 021 552 1541West Midlands B69 4HE Fax: 021 544 5520

Millpac CRS LimitedAlbion RoadWest Bromwich Telephone: 021 553 1877West Midlands B70 8BD Fax: 021 553 5507

Stnictural Sections LimitedP0 Box 92Downing StreetSmethwickWarley Telephone: 021 555 5918West Midlands B66 2PA Fax: 021 555 5659

Ward Building Systems LimitedWidespan WorksSherbumMalton Telephone: 0944 70421North Yorkshire Y0l7 8PQ Fax: 0944 70512

3.3 Manufacturers of roof deckingBritishSteel rofflesNewton Aycliffe WorksAycliffe Industrial EstateNewton Aycliffe Telephone: 0325 312 343Co. Durham DL5 6AZ Fax: 0325 312343 Ext. 217

Precision Metal Forming LimitedSwindon RoadCheltenham Telephone: 0242 527511Gloucester GL51 9LS Fax: 0242 518929

Ward Building Systems LimitedSherbumMalton Telephone: 0944 70421North Yorkshire Y0l7 8PQ Fax: 0944 70512

3.4 Manufacturers of intels

BirtleyLintels

Halesfield 9Halesfield Industrial EstateTell'ord Telephone: 0952 684763Shmpshire TF7 4LD Fax: 0952 684764

3-3



Birtley Building Products LimitedMary AvenueBirtley Teiphone: 0914106631Co. Durham DH3 1W Fax: 091 410 0650

CATNIC Components LimitedPontygwindy Estate

Caerphilly Telephone: 0222 885955MidGlamorgan CF8 2WJ Fax: 0222 867796 (Sales)0222 863178 (Reception)

Clarksteel LimitedStation RoadYaxley Telephone: 0733 240811Peterborough PE7 3EG Fax: 0733 240201

Cleveland Structural Engineering LimitedPost Box 27Yami Road Telephone: 0325381188Darlington DL1 DE Fax: 0325 382320

Hill and Smith Group of CompaniesP0 Box 4Canal StreetBiierley Hill Telephone: 0384 480084West Midlands DY5 1JL Fax: 0384 480543

I0 Lintels Limited

Avondale RoadCwmbran Telephone: 0633366811Owent NP44 1XY Fax: 0633 876222

Jones ofOswestryWhittington RoadOswestry Telephone: 0691 653251Shmpshire SY1 1 1HZ Fax: 0691 658222

Redpath Dorman Long (Manchester) Limited

32 Longwood RoadTrafford Park Telephone: 061 873 7266Manchester M17 1PZ Fax: 061 873 5539

ROM LimitedEastern AvenueTrent ValleyLichfleld Telephone: 0543 414111Staffordshire WS13 6RN Fax: 0543 268221

Stressline LimitedStation RoadStoney Stanton Telephone: 0455 272457Leicester LE9 6LX Fax: 0455 274564

3.4



3.5 Manufacturers of profiled decking for composite loorsAlpha Engineenng Services LimitedReddiffe RoadCheddar Telephone: 0934 743720Bristol BS27 2PN Fax: 0934 744131

Precision Metal Forming LimitedSwindon RoadCheltenham Telephone: 0242 527511Gloucestershire GL51 9LS Fax: 0242 518929

Quikspan Construction LimitedForelle HouseUpton RoadPoole Telephone: 0202 666699Dorset BH17 7AA Fax: 0202665311

Richard Lees LimitedWeston Underwood Telephone: 0335 60601Derbyshire DE6 4PH Fax: 0335 60014

H H Robertson UK) LimitedCromwell RoadEllesmere Port Telephone: 051 355 3622Cheshire L65 4DS Fax: 051 355 276

Structural Metal Decks LimitedMallard HouseChristchurch RoadRingwood Telephone: 0425 471088Hants BH243AA Fax: 0425471408

3.6 References1. BRITISH STANDARDS INSTITUTION

(see Section 19)

3.5



4. COMPOSITE CONSTRUCTION

4.1 ComposIte beamsFor the design of simply supported composite beams with acomposite labs, reference should

be made to the Sc! publication, Design of omposite slabs and beanis with steel decking(1).In this publication some 71 Design Tables are presented which aid the selection ofbeamsize for various plans and loadings. The natural frequency of he beams is restricted to alower limit of4 Hz and his often influences the design of the longer span beams.

The following sections highlight some important aspects ofcomposite construction. Detailsofdesign are covered in other sci Publications.

4.1.1 Long span composite beamsThere is

a strongdemand in commercial

building for onger-spanolumn-free construction

to cater foropen planning orgreater flexibility inuse. Such ong span construction willoften require deeper beams than the conventional rolled sections and in hese casesautomatically fabricated composite beams could be the solution. Moreover, since servicetrunking etc., can be accommodated either in web openings or in the case of simpleconstruction in the reduction ofbeam depth at the supports, it is often found that hereis ittle or no overall ncrease n floor depth by the use of such echniques.

Reference (2) describes modem methods ofmanufacture of automatically fabricated sectionsand gives general guidance on heir ikely range ofapplication, their erection and

economic construction. Design charts are presented and guidance given to assist nitialsizing of the structure.

Reference (3) describes salient features of haunched composite beams and puts forward adesign method consistent with BS 5950: Parts 1 and3(5) Other long span systems whichmay be used are lattice girders, and stub girders. A novel system is he parallel beam approach(6)which utilizes a two layer grillage providing continuity in orthogonal directions.

4.2 Profiled steel decking

4.2.1 Deck typesModem deck profiles are in he range of 45 to 75 mm height and 150 to 300mm troughspacing. There are two well known generic types: the dovetail profile and the trapezoidalprofile with web ndentations. A selection of he profiles available from the listedsuppliers are (see 4.3.5) shown n Figures 4.1 and 4.2

4.2.2 Slab span and depthThe most efficient use of composite slabs with permanent profiled steel decking is for heslab o span between 2.7 and 3.6 m. Slab

depths largely depend uponfire resistance

requirements and are usually between 100 and 150 mm(4). In most situationsdeflection serviceability limits are catered for if he slab span to depth ratio forcontinuous slabs does notexceed 35 for normal concrete and 30 for ightweight oncrete.For single span slabs hese ratios should be reduced to 30 and 25 respectively.

4-1



Super Holoribi

152mm.

51mr{7 [qkspan 051J

51mn4\7,\7 1SMDR51I

L 150mm I

FIgure 4.1 Dovetailed deck profiles used n composite labs

4.2.3 Steel grades and thicknessesGalvanised sheet steel is ypically 0.9 to 1.5 mm thick. Z28 steel (280 N/mm2 yieldstrength) isgenerally specified, although Z35 steel is used for some of he deeper,longer-span profiles. The thickness of galvanising is approximately 0.02 mm per face,equivalent to 275 g/m2 total coverage.

4.3 Shear connectors

4.3.1 Shear studsThe modem form ofwelded shear connection is the headed stud. The most popular size is19 mm diameter and 100mm height. Studs are often welded onto the top flange of he beamthrough he steel decking using ahand tool connected via a control unit to apowergenerator. In the case of hrough deck welding, the top flange of he beam should notbepainted or, alternatively, the paint should be removed from the zone where he shearconnectors are to be welded. Also, the galvanised steel of he decking should be less than1.25 mm thick and free from moisture.

4.3.2 Shot fliedconnectorsThe shot-fired connector hown n Figure 4.3 is often used where site power may be aproblem.

The design strength of shot-fired connectors marketed by Hilti Ltd is typically 31 kN forstandard 110 mm height connector. No reduction ismade for concrete ype and grade asfailure is largely controlled by the shear or pull-out capacity of he pins fired into thesteel beam.

4.3.3 Design strength of headed stud shear connectorsThe strength of hear connectors is a functionof he concrete strength and type, and isdetermined from the standard push-out est. The design strengths of stud shear connectorsin accordance with BS 5950 Part 3(5) are presented n Table 4.1. The use ofhigh

4-2



strength concrete snot recommended, because of ts effect on the deformation capacity ofthe shear connectors. In accordance with BS 5950: Part 3(5) the ultimate ensile strengthof he steel used in the shear connectors (before forming) should be not ess than450 N/mm2 and the elongation at failure not ess than 15%(2).

Chevron Indents

46mm[_j/\(y/ IPMF.CF46 I

225mm.-a

Horizontal Indents

55mQuikspan 0551

L 175mm J

Horizontal __________________

59mm[ ]''

Indents IRobertson OL.591

300mm.

::::cal indent

_,300mm.

—. Chevron

PMF.CF6O

L 200mm.

Circular ndentsRibdeck sol

300mm.

76mmf J/1'\,IbI olodeck

300mm.

:::: f_.s__Z._,,I. 333mm I

FIgure 4.2 Trapezoidal ded profiles used incomposite labs



-II,IiL©© IIII.,I—

IIIII

FIgure 4.3 The Hi/tishot-fired shear connector

15

2414

Table 4.1 Design strengths inkNofheaded studs n normal weight concrete

Forconcrete ofcharacteristic strength greater han 40 N/mm2 use the values of40 N/mm2.Forconnectors ofheights greater han 100 mm use the tabulated values for he 100 mm high studs.

4.3.4 LIghtweight concrete slabs

For shear tuds in lightweight oncrete density> 1750 kg/rn3) he design strengths are12.5% less than those given inTable 4.1 above.

It,0

Dimensions ofstud Characteristic strengthshear connectors (mm) ofconcrete (N/mm2)

Dia. Nominal As-welded 25 30 35 40height height

25 100 95 117 123 129 13422 100 95 95 111 106 11119 100 95 76 80 83 8719 75 70 66 70 73 7716 75 70 56 59 62 6613 65 60 35 38 39 42



4.3.5 SupplIers and manufacturersDeck manufacturers

Alpha Engineering Services LtdReddiffe RoadCheddar Telephone: 0934 743720Bristol BS27 3PN Fax: 0934 744131

Precision Metal Forming LtdSwindon RoadChelterthain Telephone: 0242 527511Gloucestershire GL51 9LS Fax: 0242 518929

Quikspan Construction LtdForellel HouseUpton RoadPoole Telephone: 0202 666699

Dorset BH17 7AA Fax: 0202 665311

Richard Lees LtdWeston Underwood Telephone: 0335 60601Derbyshire DE6 4PH Fax: 0335 60014

H H Robertson UK) LtdCromwell RoadEllesmere Port Telephone: 051 3553622Cheshire L65 4DS Fax: 051 355276

Structural Metal Decks LtdMallard HouseChristchurch RoadRingwood Telephone: 0425 471088Hants BH24 3AA Fax: 0425 471408

Ward Building ComponentsSherbumMalton Telephone: 0944 70591North Yorkshire Y017 8PQ Fax: 0944 70777

Shear connector manufacturers

Haywood Engineering Ltd17 Lower Willow Street Telephone: 0533 532025Leicester LE1 2HP Fax: 0533 514602

Hilti (GB) Ltd1 Trafford Wharf Road Telephone: 061 873 8444Manchester M17 1BY Fax: 061 8487107

TRW -Nelson Stud Welding LtdBuckingham RoadAylesbury Telephone: 0296 26171Bucks HP19 3QA Fax: 0296 22583

4.4 Welded steel fabric - BS 4483: 1985Welded steel fabric for concrete reinforcement is manufactured from plain or deformed wirescomplying with BS 4449, BS 4461 or BS 4482(e). It snormally produced rom grade 460cold reduced wire complying with BS 4482(e). Grade 250 steel is permitted orwrappingmesh. Dimensional details of the preferred ange of fabrics are given in Table 4.2.

4.5



Tabl 4.2 Dimensional details ofpreferred ange ofwelded steel abric

Fabric Longitudinal wires Cross wires Massreferences

Nominal Pitch Area Nominal Pitch Areawire size wire size

mm mm mm2/m mm mm mm2/m kg/m2Square mesh

A393 10 200 393 10 200 393 6.16A252 8 200 252 8 200 252 3.95A193 7 200 193 7 200 193 3.02A142 6 200 142 6 200 142 2.22

A98 5 200 98 5 200 98 1.54

Structural meshB1131 12 100 1131 8 200 252 10.9B785 10 100 785 8 200 252 8.14B503 8 100 503 8 200 252 5.93B385 7 100 385 7 200 193 4.53B283 6 100 283 7 200 193 3.73B196 5 100 196 7 200 193 3.05

Long meshC785 10 100 785 6 400 70.8 6.72C636 9 100 636 6 400 70.8 5.55C503 8 100 503 5 400 49 4.34C385 7 100 385 5 400 49 3.41C283 6 100 283 5 400 49 2.61

Wrapping meshD98 5 200 98 5 200 98 1.54D49 2.5 100 49 2.5 100 49 0.77

Stock sheet size Length Width Sheet area

4.8m 2.4m 11.52m2

4.4.1 Bond and lap requirementsThe anchorage engths and lap lengths of welded abric must be determined in accordancewith Clauses 3.12.8.4 and 3.12.8.5 ofBS8llO:Partl(5).

4.5 References1. LAWSON, R.M.

Design ofcomposite labs and beams with steel deckingThe Steel Construction Institute, Ascot, 1989

2. OWENS, OW.Design of abricated composite beams in buildingsThe Steel Construction Institute, Ascot, 1989

3. LAWSON, R.M. and RACKHAM, J.W.Design ofhaunched composite beams in buildings

The Steel Construction Institute, Ascot, 1989

4. NEWMAN, G.M.The fire resistance ofcomposite loors with steel deckingThe Steel Construction Institute, Ascot, 1989

5. BRiTISH STANDARDS INSTITUTION(see Section 19)

6. BRE'rF, P. and RUSHTON, J.Parallel beam approach - Adesign guide

The Steel Construction nstitute, Ascot, 19904-6



5. STEEL SLAB BASES AND HOLDING DOWNSYSTEMS

5.1 DesIgn of slab column basesThe design of teel slab column bases must be in accordance with BS 5950: Part (1)Clause

4.13 which allows he use of the following empiricalmethod

for a rectangularslabbase concentrically loaded by I, H, channel, box or RHS. The minimum thickness isgiven by:

I-

=L w(a2O.3b2)]

but not ess than the flange hickness of he column supported, where:

a = the greater projection of he plate beyond he columnb = the lesser projection of he plate beyond he columnw = the pressure on the underside of he plate assuming auniform distribution

= the design strength of he plate but not greater than 270 N/mm2

Base plates ofgrade 43A steel subject to compression only should not be limited inthickness by the brittle fracture equirements.

Gussets need not be provided o columns with slab bases but he fastenings (welds orboltedcleats) must be sufficient to transmit he forces developed at the column base connection

due to allrealistic combinations

ofactored loads

(seeBS 5950:

PartJ(1) Clause

2.2.1)plus those arising during ransit unloading and erection; the exception o this is providedin Clause 4.13.3 ofBS 5950: Part (1)•

The maximum pressure produced by the factored column oads must not exceed he designbearing strength of the bedding material or the concrete base which is normally taken as 0.4fwhere is he 28 day cube strength. The bedding materials normally usedare:

Grout: A fluid suspension ofcement with water usually of he proportion of2:1 by weight. The fluid suspension can be poured into holes and undernarrow gaps between base plates and foundations.

Sanded grout: A mixture ofcement, sand and water in approximately equal proportionsby weight. It has ahigher strength than grout butwith a lowershrinkage.

Mortar: A mixture ofcement, sand and water inproportions of about 1:3:0.4 byweight. It s ntended forplacing or packing.

Fine concrete: A mixture ofcement, sand, coarse aggregate and water inproportions ofabout 1:11/4:2:0.4

by weight.The coarse

aggregate has amaximum size of10mm.

Table 5.1 provides suggested design bearing strengths ofbedding material.

Unless proper provision is made for he placing and compaction of good quality mortar orconcrete, the bearing strengths appropriate to grout or sanded grout should be adopted inthe design. In he common case where grout is required o be introduced into bolt pocketsunder acolumn base plate, the access space is often between 25 and 50 mm; thus placingconditions are poor and correspondingly low bearing strengths should be assumed.

5-1



Detailed guidance on manufacture and placing procedures to achieve the values given inTable 5.1 is given in Reference (2).

Table 5.1 Design bearing strengths ofbedding material

Bedding material Cube strengthat 28 days f Design bearing strength

at 7 days 0.4

Grout

Sandedgrout

Mortar

Fine concrete*

N/mm2

12.0 -15.015.0-20.0

20.0-25.0

30.0 -50.0

N/mm2

4.8 - 6.06.0- 8.0

8.0-10.0

12.0 -20.0

•The strength of ine concrete depends criticallyon he degree ofcompactionwhich can be achieved. Higherbearing strengths up to 30.0 N/mm2 can beobtained using hammered ordr/packed ine concrete.

Further nformation and detailed guidance for the design ofcolumn bases is given inManual on connections, 2nd edition(3).

An alternative method ofchecking the adequacy of he thickness ofbase plate isgiven in arecent publication by SCJ/BCSA, Joints insimple onstruction, Volume 1: Design methods4).The minimum thickness is given by:

r 061CU 1t =KL Pyp

but not ess han he langehickness

of he supported column, where K isdefined

inFigure 5.1, being the distance from the edge of he column section to provide he requiredminimum base plate area.

T = hickness of flanget = hickness ofweb

Areq= required area ofbase plate

FIgure 5.1 Required minimum area ofbase plate

5-2

-E

T



5.2 Concentric oad capacity of slab bases for universal columnsThe load capacities or grade 43 steel slab bases with universal columns are given inTables 5.2 to 5.8 inclusive. The tables are based onBS 5950: Part J(1) Clause4.13.2.2. In using the tables, note hat:

(I) F = the factored column axial load inkN

(ii)W = pressure (N/mmZ)

producedby the factored load F on the underside of slab base

(iii) Plate projections a and b are for he lightest section in any particular columnserial size

(iv) It s mportant o check hat the thickness of he slab isnot ess than the thicknessof he flange of he respective universal column as this restriction could not beconsidered in he preparation of he tables.

5.3 HoldIng down systemsThe design of he holding down system and he foundation isbest prepared under the

direction ofa single engineer who has an appreciation of he steelwork design, erectionproblems and civil engineering oundation construction. If his unified approach isnotpossible then it is essential hat he steelwork designer and concrete foundation esignerswork inclose co-operation.

The design of he holding down system must cater for:

(i) the transmission of he service oads from the column o the foundations

(ii) the stabilisation of he column during erection

(iii) the provision of ufficient movement to accommodate the fabrication and erectiontolerances

(iv) the system ofpacking, illing and bedding

(v) the provision ofprotective methods which ensure he achievement of he design ifeof he holding down system.

Full nformation with regard to the design ofholding down systems is given in Reference (2).

5.4 DrawIngsIt sessential hat all the information needed both by the stcelwork erection and civilengineering foundation contractors should be given in the drawings with all the assumptionsclearly stated.

5-3



TabI. 5.2 Grade 43steel base plate concentnc oad and bearing capacity foruniversalcolumns 152 x 152 UC series

Slab 300 x 300mm

350 x350mm

400 x400mm

450 x450mm

500 x500mm

thicknessmm

W FN/mm2 kN

W FN/mm2 kN

W FN/mm2 kN

W FN/mm2 kN

W FN/mm2 kN

10

15

20

25

30

35

2.36 212

5.31 478

9.27 834

14.5 1300

2.96 363

5.17 633

8.08 990

11.6 1430

3.29 527

5.15 823

7.41 1190

10.1 1610

3.56 721

5.13 1040

6.98 1410

3.76 940

5.12 1280

T.bl. 5.3 Grade 43 steel base plate concentric load and bearing capacity or universalcolumns 203 x203 UC series

Slab 400 x400mm

450 x450mm

500 x500mm

600 x 600mm

700 x700mm

thicknessmm

W FN/mm2 kN

W FN/mm2 kN

W FN/mm2 kN

W FN/mm2 kN

W FN/mm2 kN

15 2.99 478

20 5.21 834 3.31 671

25 8.15 1300 5.18 1050 3.58 895

30 11.7 1880 7.46 1510 5.16 1290

35 16.0 2550 10.2 2060 7.02 1750 3.93 1410

40 20.9 3340 13.3 2690 9.17 2290 5.13 1850

45 15.5 3140 10.7 2680 6.00 2160

50 13.2 3310 7.41 2670 4.73 2320

55 8.97 3230 5.72 2800

60 6.81 3340

5.4



TibI.5.4 Grade 43steel base plate concentric oad and bearing capacity or universalcolumns 254 x254 UC series

Slab 500 x500mm

550 x550mm

600 x 600mm

700 x 700mm

800 x 800mm

thicknessmm

W FN/mm2 kN

W FN/mm2 kN

W FN/mm2 kN

W FN/mm2 kN

W FN/mm2 kN

20 3.34 83425 5.21 1300 3.60 1090

30 7.51 1880 5.18 1570 3.79 1370

35 10.2 2550 7.06 2130 5.17 1860

40 13.3 3340 9.22 2790 6.75 2430

45 15.6 3900 10.8 3260 7.89 2840 4.75 2330

50 19.3 4820 13.3 4030 9.75 3510 5.87 2870

55 23.3 5830 16.1 4870 11.8 4250 7.10 3480 4.74 3030

60 19.2 5800 14.0 5050 8.45 4140 5.64 3610

65 22.5 6810 16.5 5930 9.91 4860 6.61 4230

70 19.1 6880 11.5 5630 7.67 4910

75 13.2 6470 8.81 5640

TabI. 5.5 Grade 43steel base plate concentric oad and bearing capacity or universalcolumns 305 x305 UC series

Slab 550 x550mm

600 x 600mm

700 x 700mm

800 x800mm

900 x900mm

1000 x 1000mm

thicknessmm

W FN/mm2 kN

W FN/mm2 kN

W FN/mm2 kN

WN/mm2

FkN

WNImm2

FkN

WN/mm2

FkN

20 3.32 1010

25 5.19 1570 3.59 1290

30 7.48 2260 5.17 1860

35 10.2 3080 7.03 2530 3.93 1930

40 13.3 4020 9.19 3310 5.14 2520

45 15.6 4710 10.8 3870 6.01 2950

50 19.2 5810 13.3 4780 7.42 3640 4.73 3030

55 23.2 7030 16.1 5780 8.98 4400 5.73 3670

60 19.1 6880 10.7 5240 6.82 4360 4.72 3820

65 22.4 8080 12.5 6150 8.00 5120 5.54 4490

70 14.5 7130 9.28 5940 6.43 5210 4.71 4710

75 16.7 8180 10.6 6820 7.38 5980 5.41 5410

80 19.0 9310 12.1 7750 8.39 6800 8.16 6160

85 21.4 10500 13.7 8750 9.48 7680 6.95 6950

90 15.3 9810 10.6 8610 7.79 7790

5-5



Table 5.6 Grade 43 steel base plate concentric load and bearing capacity or universalcolumns 356 x368 UC series

Slab 600 x 600mm

700 x 700mm

800 x800mm

900 x900mm

1000 x 1000mm

1100 x 1100mm

thicknessmm

W FN/mm2 kN

W FN/mm2 kN

W FN/mm2 kN

W FN/mm2 kN

W FN/mm2 kN

W FN/mm2 kN

20 3.24 1170

25 5.06 1820

30 7.29 2620 3.71 1820

35 9.92 3570 5.06 2480

40 13.0 4670 6.60 3240

45 15.2 5460 7.73 3790 4.67 2990

50 18.7 6740 9.54 4670 5.77 3690

55 22.7 8150 11.5 5660 6.98 4470 4.67 3780

60 13.7 6730 8.31 5320 5.56 4500

65 16.1 7900 9.75 6240 6.52 5280 4.67 4670

70 11.3 7240 7.57 6130 5.42 5420

75 13.0 8310 8.69 7040 6.22 6220 4.67 5650

80 9.88 8000 7.07 7070 5.31 6430

857.99 7990 6.00 7260

90 6.72 8140

Tubie 5.7 Grade 43steel base plate concentric oad and bearing capacity or universalcolumns 356 x406 UC series (up to393 kg/rn)

Slab 700x700mm

800x800mm

900x900mm

l000xl000mm

llOOxllOOmm

1200x1200mm

thicknessmm

W FN/mm2 kN

W FN/mm2 kN

W FN/mm2 kN

W FN/mm2 kN

W FN/mm2 kN

W FN/mm2 kN

35 5.86 2870

40 7.65 3750 4.47 2860

45 8.96 4390 5.24 3350

50 11.1 5420 6.46 4140 4.23 3430

55 13.4 6560 7.82 5010 5.12 4150

60 15.9 7800 9.31 5960 6.10 4940 4.30 4300

65 18.7 9160 10.9 6990 7.16 5800 5.05 5050

70 21.7 10600 12.7 8110 8.30 6720 5.86 5860 4.35 5270

75 14.5 9310 9.53 7720 6.72 6720 5.00 6040

80 16.5 10600 10.8 8780 7.65 7650 5.68 6880 4.39 6320

90 20.9 13400 13.7 11100 9.68 9680 7.19 8700 5.55 8000

100 16.9 13700 12.0 12000 8.88 10700 6.86 9870

5-6



Table 5.8 Grade 43steel base plate concentric oad and bearing capacity foruniversalcolumns 356 x406 UC series (above 393 kg/rn)

Slab 900x 00mm

l000x 1000mm

llOOx 1100mm

1200x 1200mm

1300x 1300mm

thickness

mmW FN/mm2 kN

W FN/mm2 kN

W FN/mm2 kN

W FN/mm2 kN

W FN/mm2 kN

60

65

70

75

80

90

100

6.78 5500

7.96 6450

9.23 7480

10.6 8590

12.1 9770

15.3 12400

18.8 15300

4.70 4700

5.52 5520

6.40 6400

7.35 7350

8.36 8360

10.6 10600

13.1 13100

4.70 5680

5.39 6520

6.14 7420

7.76 9400

9.59 11600

4.69 6760

5.94 8550

7.33 10600

4.69 7930

5.79 9790


(see Section 19)

2. "Holding down systems for steel stanchions"Concrete Society, BCSA and Constrado, London, 1980

3. PASK,J.WManual on connectionsVolume 1 - Joints in simple construction (conforming with the requirements ofBS 5950:Part 1:1985)The British Construction Steelwork Association, Publication No. 19/88, London, 1988

4. THE STEEL CONSTRUCTION INSTITUTE/B CSAJoints in simple construction, volume 1: Design methodsSC!, Ascot, 1991

5-7



6. BUILDING VIBRATIONS

6.1 IntroductionThe dynamic esponse ofvibrations in buildings has increased in recent years with thegreater use of lightweight materials and more economic design, and large forces acting ontall structures. Vibration problems can be divided nto two main categories; those inwhich the occupants or users of he building are nconvenienced, and those in which heintegrity of the structure may be prejudiced. Vibration can also have a serious effect onlaboratory work and trade processes.

6.2 Vibration ofbuildingsThere are three aspects o consider when vibrations ofabuilding are of oncern; thesource causing he forces which nduce vibration, the response of he

building,or elements

of he building, to those forces, and the acceptable response level.

6.2.1 VIbration sources

Sources which cause buildings to vibrate fall into two main categories; those which arerepetitive (and very often caused by some man-made agency), and those which are random andoften caused by natural sources). Typical sources ofman-made vibration are machinery,compressors, piledrivers, road and rail traffic, and aircraft natural sources ncludewind, earthquakes and wave action. In the United Kingdom wind is by far the most commonsource ofnaturally occurring vibration energy. The occurrence of repetitive loading, suchas that caused by machinery is rarely aproblem or he integrity ofa structure, unlessthe frequency coincides with anatural frequency of some element of he building. Theeffect on occupants, however, may be unacceptable as this may occur at response levels wellbelow that causing structural damage.

6.2.2 BuIlding responseThe esponse of buildings to a vibration source isgoverned by the following factors:

(a) the relationship between henatural frequencies of the building (and/or elements of

the building) and the frequency characteristics of he vibration source;

(b) the damping of he resonances of the building orelements;

(c) the magnitude of he forces acting on the building;

Some guidance on natural requencies ofbuilding elements is available inReferences (1)and(2).

Damping values are more difficult o evaluate; generally, in the absence ofmeasurement,specialist advice should be sought. Some guidance on values applicable to tallerstructures is available inReferences 3) and (4).

Specialist advice on stiffness, he magnitude of orces and the interaction ofbuildingswith the medium transmitting the forces should be sought. Some nformation can be found nthe literature, References (4) to (8).



6.3 Vibration of floorsThe problem offloor vibration due to pedestrian raffic is adequately covered n theDesign guide on the vibration of loors(9). This publication presents guidance forthe design of loors in steel framed stnictures against unacceptable vibrations caused bypedestrian raffic with pailicular elevance to composite floors with steel decking.

6.4 Human reactionHuman eaction o the levels of accelerations that are typical inbuildings and floors is arather fuzzy subject, not due to lack ofdata but because reaction s almost entirelyrelated to psychological factors rather han physiological factors. Individuals varygreatly n their assessments and here may be differences between nationalities. It alsovaries according o the task hat the person is engaged upon and to other environmentalstimuli (e.g. sight and sound) which may or may not be connected with the source ofvibration.

The most relevant UK specification is BS 6472: Evaluation ofhuman exposure to vibrationin buildings (1 Hz to 80 Hz)(10). It defmes a root-mean-square (r.m.s.) accelerationbase curve for continuous vibration and multipliers to apply in specific circumstances.

The qualitative description ofhuman reaction o sustained steady oscifiation isgiven inFigure 6.1

10 //Qun/1.0 Strongjy perceptible —

tiringoverlong penods

CClearly perceptible —

distracting

0.1Perceptible

0.010.1 B:re

erce:tible

Frequency (Hz) (log scale)

FIgure 6.1 Human sensitivity, veitical vibrations (peisons standing)



6.5 References1. ELLIS, B.R.

An assessment of the accuracy ofpredicting the fundamental natural requencies ofbuildings and the implication oncerning the dynamic analysis of structuresProceedings Institution ofCivil Engineers Part2, London, 1980, 69, pp763-776

2. STEFFENS, R.J.Structural vibration and damageBuilding Research Establishment, Watford, 1974

3. JEARY, A.P. & ELLIS, B.R.Recent experience of nduced vibration of structures at varied amplitudesProc. ASCEIEMD Conference on Dynamic esponse of tructures,Atlanta, GA, January 1981. Available in Reference (4)

4. HART, G.C.Dynamic esponse of structures: experimentation, observation, prediction and controlAmerican Society ofCivil Engineers, 345 E47 Street, New York, NY,USA, 10017 1980

5. ENGINEERING SCIENCES DATA UNITItem 76001, Response of lexible structures to atmospheric turbulenceESDU, 251-259, Regent Street, London, 1976

6. ENGINEERING SCIENCES DATA UNITItem 79005, Undamped natural_vibration of hear buildingsESDU, 251-259, Regent Street; London, 1979

7. JEARY, A.P.The dynamic behaviour of he Arts Tower, University ofSheffield and ts implicationsto wind oading and occupant eactionBRE Current Paper CP48 78Building Research Establishment, Watford, 1978

8. BUILDING RESEARCH ESTABLISHMENTVibrations: building and human responseBRE Digest 278BRE, Watford, 1983

9. WYATF, T.A.Design guide on the vibration of floorsThe Steel Construction Institute, Ascot, 1989

10. BRITISH STANDARDS INSTITUTION(see Section 19)



7. EXPANSION JOINTS

7.1 BackgroundThree points are noteworthy concerning he provision ofexpansion joints in steel-framedbuildings:

• They are potential sources ofproblems.• The advice circulating on heir provision and spacing svariable and conflicting.• It is widely reported hat they do not move anyway.

Varying advice is given in References (2) to (7), so the basics of he problem will firstbe considered before giving any recommendations.

7.2 BasIcs

7.2.1 GeneralWhen emperatures hange, materials expand and contract, generally expanding astemperatures ncrease. Steel has a positive coefficient of inear thennal expansion, whichis quoted inBS 5950: Part 1: 1990(1) (Clause 3.1.2) as 12 x 10-6 per °C.

This code also recommends (in Clause 2.3) that, where it snecessary o take account oftemperature effects, the temperature range to be considered for internal steelwork n theUK can be taken as from -5°C to +35°C, hat isa otal range of40°C oravariation romthe mean of±20°C. It is commonly assumed that the foundations do not move and thus thereis a differential movement problem, with the steel frame rying to expand but he column

bases remaining static. Simple analysis methods or computer programs can most readily beused to account for his by solving he reverse problem, n which he steelwork ries toremain he same length but he bases are displaced horizontally (see Figure 7.1) so theexpansion of he frame is reated as a reversed imposed displacement of he bases.

Theoretically here are two alternative approaches:• Free expansion• Restraint of hennal expansion.

Inpractice an intennediate situation often actually occurs, which is generallyadvantageous. But before moving on to such practical factors, it is useful to examinethese two limiting cases and the calculations involved.

7.2.2 Free expansionFor simple construction, in which all the joints are assumed o be pinned, he analysisdescribed above does not provide any forces or moments and the calculated expansion issimply treated as adeflection, which is greatest at the columns urthest rom the bracedbay.

For both simple and continuous construction, the non-verticality ofcolumns other than atthe centre of expansion) will lead to additional orces, moments also ansing in continuousconstruction, though both the forces and the moments due to displacement are oftenneglected as "secondary ffects". To ustify this the overall ength of structure slimited, or broken down into separate sections separated by expansion joints. In simpleconstruction, each such section needs its own (central) braced bay.

7-1



L L

(a) Initialposition at mean temperature.

L÷ iL. L+

2L

EL

LL11

1a1

(b) Position after expansion of steelwork.

= a.AT.L= Temperature ise

a = Coefficient ofexpansion

L L

£2L-2L

1(C) Model for computer analysis.

Figure 7.1 Assumptions forcalculating expansion effects

For a20°C emperature change, the expansion per metre length is20 x 12 x 10-6 x 10= 0.24 mm permetre length. For abuilding length (overall or between expansion joints) of100 m, the free expansion length would be taken as 50 m (neglecting any constraint withinthe braced bay) so each end would move 0.24 x 50= 12 mm, orpro rata for other engths.

In an ndustrial building with aheight of (say) 6 m, this represents adisplacement of 1

in 500. In acommercial building with a storey height of say) 3.6 m the displacementwouldbe 1 in300.

Of course n either case the total calculated movement in an expansion joint would bedouble the maximum movement ofone section, that is 24 mm for a spacing of 100 m.Considerations of acceptable movements in expansion joints or loors have thus lead torecommendations to introduce expansion joints every 50 m, thus limiting heoretical jointmovements to ±12 mm and theoretical displacements in a3.6 m storey height to 6mm i.e. 1 in600.

7-2

T



On theother hand expansion joints in the cladding of industrial buildings can be devisedwith arger movement capacities. For industrial buildings, recommended spacings ofexpansion joints from 80m to 150 m have been proposed, representing expansion ointmovements ofabout 19 to 36 mm and theoretical displacements in a 6 m height of 1 in 632 to1 in333. For higher buildings he slope wifi be less.

This discussion ndicates how various "rule-of-thumb" recommendations have arisen and whythey vary so much. It also serves to warn against applying ules devised forone situation

to entirely different circumstances, without proper consideration ofwhat actually happens.

But the real situation sdifferent, as will be explained in the following sections.

7.2.3 Constraint of thermal expansionIfnstead ofallowing ree expansion, it is prevented by some appropriate means, a stressis induced. Using the value of he elastic modulus of steel E from BS 5950: Part ](1)

Clause 3.1.2 of205 kN/mm2 he stress for a20°C temperature change is20 x 12 x 10.6 x205 x 10 = 49.2 N/mm2or about 50N/mm2.

BS 5950: Part 1(1) (Table 2) recommends ayf factor of 1.2 forforces due to temperatureeffects, giving a factored load stress of60Nfmm2. Thus even where expansion is almostcompletely inhibited, the stress nduced is well within the range that can be resisted bysteel members, provided they are not so slender hat hey buckle.

The Code isnot clear on combining thermal effects and mposed loads, but it is consideredthat ay actor of 1.2 could also be applied o the imposed oads when consideringcombined effects. It should also be noted that whilst ncluding mposed roof oads due osnow may be necessary for hermal contraction (i.e. negative hermal expansion), it is notusually a realistic load case forpositive thermal expansion!

Buckling due to thermal expansion is self-limiting because the force dissipates as themember deforms. The resulting deformation is clearly unacceptable in crane rails, cranegirders, runway beams and valley beams, and s probably not acceptable in eaves beams.

However tdoes not ead directly o failure and may be tolerable where he appearance isunaffected.

7.3 Practical factors - industrial buildings

7.3.1 DescriptIonThe term "industrial building" isused here to describe a single storey factory or storagebuilding with a steel frame and a sheeted roof. The sides may be either sheeted, brickclad or amixture of both. Itmay also possibly have an overhead crane gantry or runwaybeams.

7.3.2 ExaminatIon ofassumptionsThe assumptions mentioned n Section 7.2.1 are worth examining critically. For example ifthe steel columns are supported on concrete bases which are jointed by "ground beams" or

even ust by a floor slab (let alone cases where a raft foundation isused), why should heframe expand but he bases remain unmoved? Assuming they do, there must be restraint romthe ground, producing stresses n he foundations. If his is acceptable, why not acceptthermal stresses n the superstructure?

Moving up a sheeted building, he lowest ine ofsheeting rails isquite close to groundlevel. So if he bases do not move, this line of sheeting rails must be heavily restrained,even if he roofsteelwork can expand freely. If his is acceptable, why not acceptrestraint of sheeting ails atother evels?

7-3



7.3.3 PItched raftersModem ndustrial buildings often have pitched roofportal frames or similar ypes of oofframing which do not nclude horizontal members. If hennal expansion of hese frames isresisted at ground level, the effect is to increase the horizontal thrust and the apex ofthe frame rises; fora emperature drop it falls. Thus in the plane of such frames,expansion joints in the steelwork are unnecessary. Provided that the roof sheeting is ableto expand, the most that needs consideration is the additional stresses n the frames.

7.3.4 Clearance holesHoles for bolts are normally 2 mm larger han the nominal bolt diameter, more for argesizes. Theoretically this allows a total of4 mm relative movement between amember and acleat or gusset plate which attaches t to supporting members, that is ±2 mm. Howeverbolt holes are notnecessarily precisely spaced and in practice the available movement isless, say ± 1 mm. Purlins and sheeting ails are often continuous over 2 bays for spans upto 5 m; so the likely movement is ± 1 mm at each end ofa 10 m length, that is a total of2mm in a 10 mlength, compared to athermalexpansionfor±20°Cof±20 12 x l0-6x 10x l03=±2.4mm.

The force generated in a ypical purlin or sheeting ail at 60 N/mm2 is also of a similarmagnitude to the force needed to cause slip in a ypical bolted connection, so it isnotclear-cut whether he available movement gets utilised or not, even where free expansion isprevented. However, it can be seen that the available movement should generally besufficient to avoid significantly higher stresses being generated for any reason.

7.3.5 ProvisIon of braced baysTo permit ree expansion, the logical arrangement would be to provide avertical braced bayat mid-length, with bracing in end bays restricted to roof bracing. However in practicethe end bays have frequently been braced vertically for convenience, and this is now theusual practice recommended for safety during erection. Even where such bracing is houghtofas temporary bracing, it is rarely removed n practice.

The result is hat most such buildings do in fact constrain hermal expansion, even thoughthis might not always have been consciously intended or explicitly allowed for n thecalculations. In recent years buildings several hundred metres long have been constructedwith braced bays at ntervals, but with no expansion joints.

7.4 PractIcal factors - commercial buildings7.4.1 DescrIptionThe term "commercial building" sused here to describe amulti-storey office block orsimilar building used as a retail shop, school, hospital etc. The floors are generallyconcrete, ormore likely nowadays, composite slabs. The external cladding may be brickworkor various kinds ofpanels, such as precast concrete, composites orcurtain walling.Internal partition walls are likely to include brickwork orblockwork as well as moveablelightweight partitions.

7.4.2 ExamInation of assumptIonsAs discussed n Section 7.3.2 there is no reason o prefer free expansion rather hanrestraint of expansion. Also for acommercial building, once the building is completed therange of emperature change experienced by the internal steelwoit isunlikely o exceed± 15°C and while the building is innormal use the variation snot ikely to exceed ± 10°C.

7-4



7.4.3 ContInuous constructionInstnictures ofcontinuous constniction ree expansion isnot possible due to the rigidityofcontinuous members and the joints. The result is acondition ntennediate between reeexpansion and full constraint ofexpansion, with reduced movements due to the momentsgenerated in the frame. The extent of his partial constraint depends on the bendingstififiesses of he members, particularly the columns, and the cross-section areas oflongitudinal members and floor slabs constrained.

7.5 Cladding and partitions7.5.1 SheetingSheeting, particularly metal sheeting, can easily experience a arger temperature changethan the internal steelwork. The maximum temperature depends largely on the colour andother heat absorption characteristics. The minimum temperature depends on environmentaland climatic actors.

For profiled steel sheeting, expansion transverse to the span can readily be accommodated by"concertina" or "breathing" action. Parallel o the span, care needs to be taken wherelong lengths of sheeting are used. Some movement can be accommodated by the fixings to thepurllns and by movement of he purlins, depending on the nature of he purlin-to-rafterconnections.

7.5.2 BrIckwork and biockworkBrickwork and blockwork have a different coefficient of hermal expansion to steelworkand reinforced concrete, so the main problem sdifferential expansion. There are alsosignificant differences between different types of brickwork.

Expansion joints have to be provided n the brickwork at elatively close centres, asrecommended in Clause 20 and Appendix A of BS 5628: Part (1)• These also allow forshrinkage effects.

Provided hat expansion joints are provided n supported brickwork at he recommendedcentres, here is no need forexpansion joints in the steel frame.

External brickwork cladding to single-storey or low-rise buildings soften supportedvertically by foundations but supported horizontally against wind forces by the steelframe, with horizontal deflections of the steelwork accommodated by a flexible damp-prooflayer at the foot, see Clause 20 ofBS 5628: Part3(1) and also Section 8.5.2. In hiscase the free expansion of he steelwork may need to be either imited or constrained.

7.5.3 Floor slabs

Inmodern steel-framed buildings, the floor slabs are often composite slabs. No particularneed for expansion joints in such floors has been reported, butjoints are usuallyintroduced at suitable points such as locations of ignificant changes n the shape of hebuilding on plan or n he overall height or in the floor levels, or in the type offoundation. Similar considerations also apply to reinforced orprecast concrete loors,seeBS 8110: Part2(1).

7.6 Detailing of expansion joints7.6.1 Joints n external sheetingThe precise details of uch oints depends on the type of sheeting and the internal andexternal conditions.

7-5



What should be noted is hat the provision of a satisfactory expansion joint is neithercheap nor simple. This iswhy it is often better to spend more on the structure o avoidthe need for a oint. Where one is provided t isa false economy to try to make savingsin its construction.

7.6.2 JoInts In brickworkand biockworkReference should be made to BS 5628: Part 3(1) and to specialist recommendations(4).

7.6.3 JoInts in floor slabs

Once a oint na floor slab is provided, it may tend to act as a focus or collecting pointformovements due to avariety of causes, such as creep and settlement and may also need totake up the effects ofconstruction tolerances and differential sways. Such oints shouldtherefore permit more than the maximum theoretical expansion movement and a minimum of22 mm is suggested.

7.6.4 JoInts Insheeting aIls and purllns

Where expansion oints are provided in sheeting ails and purlins, slotted holes may beused but special bolts designed to permit free movement without he nut coming oose (suchas shouldered bolts) should be used and care should be taken to ensure hat slots aresmooth enough o permit free movement.

7.6.5 JoInts In crane girders and runway beamsWhere it is necessary for overhead crane gantries to cross expansion joints, specialdetails are necessary both to permit free movement and o avoid rail wear. The twoadjacent girders are best supported separately, though ahalving-joint with a sliding

bearing is also possible. The rail should have a long scarving oint-

and where craneutilisation shigh it is wise to make provision for easy replacement of the expansionjoint n the rail, as wear is likely obe high at this point.

Runway beams should preferably not cross expansion joints, unless hey have flexiblesupport arrangements which can accommodate support movements without he need for abreak in the runway beam itself.

7.6.6 Other joints In steelworkInsteel members larger han sheeting ails and purlins, simple slotted hole joints areunlikely to work and sliding bearings are unlikely to be economic except perhaps in cranegirders.

Articulated joints can sometimes be used in lattice girder roof construction, but in mostcases the most practical solution sa complete break in the framing. Double columns closetogether are best avoided but can be used where here is no alternative. But by arrangingjoints at changes in layout or level of he building, it is generally possible to haveseparate structures which are sufficiently far apart not to cause problems but sufficientlyclose to enable he gap to be bridged by cantilevering.

7.7 Recommendations7.7.1 General

Expansion joints should be used only where they are really necessary. The alternative ofresisting expansion should be considered as an alternative. Where expansion joints areprovided, they should beproperly detailed to ensure hey can move and also to ensure theycannot cause leaks in the cladding or problems in floors etc.

7-6



7.7.2 Steel frames - Industrial buildingsUnless longitudinal members such as eaves beams and crane girders are designed to resiststresses due to restraint ofexpansion, provide expansion oints in the steel frame at amaximum of 150 m centres, or 125 m centres in buildings subject o high internaltemperatures due to plant(5).

Vertical braced bays should be positioned mid-way between expansion oints, but plan bracingcan be located at gables. Ifvertical braced bays are needed at the ends, allow forstresses in main ongitudinal members due to restraint ofexpansion and also in bracingexcept where deformation by self-limiting buckling can be accepted).

In he transverse direction, expansion oints should be provided where the roofconstruction includes horizontal members, but may be omitted where flexure ofpitchedrafters permits horizontal movement, hough he associated hrust should be accounted forin the analysis.

Expansion joints should pass through he whole structure above ground evel without offsets

so as to divide the structure nto individual sections. These sections should be designedto be structurally independent without relying on stability ofadjacent ections.

To prevent unsightly damage and rain penetration, the joint should be designed and detailedto beproperly ncorporated in the finishes and external cladding.

7.7.3 Steel frames -commercial buildingsExpansion oints should be considered where he width or length of he building exceeds100 mm the case of imple construction or 50 m for continuous construction(2).

They should also be considered in buildings of esser overall dimensions, where here aresignificant changes n shape on plan or in he overall height or n the floor levels.

In simple construction, vertical bracing systems must be provided foreach portion when hebuilding is split by expansion joints. These should preferably be located midway across therelevant portion.

The effects ofdifferential horizontal displacements causing non-verticality of columnsremote from bracing systems should be considered and the resulting forces n connectedhorizontal members should be catered or. If hese are excessive, closer ointspacing may

be preferable.

Incontinuous construction the steel frame is subjected to forces due to restraint of hethermal expansion of the floor slabs. The coefficient of hermal expansion of reinforedconcrete can be assumed to be 10 x 10-6 per °C. Avalue of he modular ratio for concreteae of7 fornormal weight concrete or 11 for lightweight aggregate structural concrete (seeBS 5950: Part3: Section 3.1(1)) is appropriate or thermal effects. A reducedtemperature variation of ± 10°C is adequate during normal use, but should be combined withimposed load effects using Yf= 1.6 for he imposed loads in this case, rather han 1.2.

Where he provision ofexpansion joints is mpractical or uneconomic (such as in the caseof a tall multi-storey building) the resulting orces, ncluding those due to expansion ofthe floor slabs, need to be accounted for. However, in a all building, t is usually onlythe lower storeys that are significantly affected.

In he case of lat roofs where significant solar heating of he structure upporting theroof spossible, additional expansion joints should be considered in he op storey. Wherethey are needed, simple construction should be considered for the top storey, even if helower storeys are of continuous construction. If his isnot convenient, other possibilitiesare either o introduce nominally pin-jointed simple connections between he columns andthe roof beams, even if he beams are continuous, or else to use nominal pin oints in thecolumns at top floor evel.

7-7



Expansion joints should pass through he whole structure above ground level without offsets,so as to divide he structure into ndividual sections. These sections should be designedto be structurally independent without elying on stability ofadjacent ections.

Expansion joints should be at east 22 mm wide, or larger where necessaiy. The expansionand contraction characteristics of he joint iller material isusually such hat onlymovements of±30% of the overall oint width can be accommodated.

To prevent unsightly damage and rain penetration, the oint should be designed and detailedto be properly ncorporated in he finishes and external cladding.

7.7.4 Root sheetingContinuous lengths of steel roof sheetingofup to 20 m, measured down the slope, can beused without special provisions. However, for onger lengths t is advisable to makeprovision for expansion of he sheeting elative to the supporting frame. This can be doneeither by allowing orminor ovalling of the holes in the sheeting by using specialenlarged neoprene washers, orby providing more flexible purlin-to-rafter connections, orelse by making use of standing seam" type roof sheeting. However when standing seamsheeting sused it is necessary o ensure hat adequate lateral restraint s given to thepurlins by other means.

7.7.5 BrIck or block walls

Expansion joints must be introduced into all brick or block walls, whether internal orexternal, at the spacings recommended in Clause 20 of BS 5628: Part3(1). These varyfrom 6m to 15 m according to the type ofbrick orblock.

7.8 SummaryAsummary of he recommendation outlined in Section 7.7 isgiven in Table 7.1.

Table 7.1 Maximum spacing ofexpansion joints

Steel rames -industrial buildings

generally 150 m

buildings subject o high nternaltemperatures due to plant

125 m 1

Steel rames - simple construction lOOmcommercial buildingcontinuous construction 50 m 2

Roof sheeting down the slope 20 m

along he slope no limit

Brickor block walls clay bricks 15 m

calcium silicate bricks 9 m

concrete masonry 6 m

Notes:

[1] Where the stress due to constraint of hermal expansion can be catered orby the members, no imit s necessary n simple construction.

[2] Larger spacings are possible where he stresses due toconstraint of hermalexpansion can be catered orby the members.

[3] Longer engths are possible where provision orexpansion s made.

[4] Formore detail see Clause 20 and Appendix A ofBS 5628: Pail 3, see Reference (1).

7-8



7.9 References1. BRITISH STANI)ARDS INSTiTUTION

(see Section 19)

2. BRITISH CONSTRUCTIONAL STEEL WORK ASSOCIATIONMulti-storey steel structures: A study on perfonnance criteria

Publication No 13/84BCSA, London, 1984

3. LAWSON, R.M. and ALEXANDER, S.J.Design for movement in buildingsCIRIA Technical Note 107CIRIA, London, 1981

4. BRICK DEVELOPMENT ASSOCIATION/BRITISH STEELBrick cladding o steel framed buildingsBrick Development Association ndBritish Steel Corporation Joint Publication, London,September 1986

5. AMERICAN INSTITUTE OF STEEL CONSTRUCTIONEngineering orsteel construction: A source book on connections, Chapter 7, page 7-8AISC, Chicago, 1984

6. THE INSTITUTION OF STRUCTURAL ENGINEERS & THE INSTITUTION OFCIVIL ENGINEERSManual for the design of teelwork building structuresThe Institution of Structural Engineers, London, 1989

7. FISHER, J.M. and WEST, M.A.Serviceability design considerations for ow-rise buildingsSteel Design Guide Series No 3American Institute ofSteel Construction, Chicago, 1990



8. DEFLECTION LIMITS FOR PITCHED ROOFPORTAL FRAMES

8.1 BritIshStandard recommendations:BS 5950: Part 1: 1990(1) recommends in Clause 2.5.1 that:

"The deflection under serviceability loads ofa building or pait should not impair hestrength orefficiency of the structure or its components orcause damage o thefmishings.

When checking fordeflections the most adverse ealistic combination and arrangement ofserviceability loads should be assumed, and the structure may be assumed to be elastic.

Table 5 gives recommended limitations forcertain structural members. Circumstances mayarise where greater or lesser values would be more appropriate. Other members may alsoneed adeflection imitation o be established, eg. sway bracing.

Generally he serviceability loads may be taken as the unfactored imposed oads. Whenconsidering dead load plus imposed load plus wind oad only 80% of he imposed oad andwind oad need be considered. In the case ofcrane surge and wind, only the greatereffect ofeither need be considered in any load combination."

The firstparagraph gives the basic criteria, applicable o all structures. Generally, morespecific criteria are then given in Table 5.

However, Table 5 specifically excludes portal frames. This isdue o the fact hat hedeflections ofportal frames have no direct significance for he serviceability of heportal frame tself, whereas their implications for the serviceability of he claddingdepend on the type ofcladding and other constructional details outside he scope of hecode.

Guidance has therefore been ncluded in his publication to assist designers in providingsuitably serviceable steel portal frames to satisfy he basic cntena given in paragraphone ofClause 2.5.1.

It should be noted thatportal frames which give large deflections may also have problemswith frame stabifity at the ultimate limit state, but his is covered separately in the code.

8.2 Types ofcladding8.2.1 SIde claddingAdistinction must be drawn, first of all, between buildings with their sides clad withsheeting and hose with walls comprising brick, block or tone masonry orprecast concretepanels. It s to be recognised ofcourse hat various combinations of cladding are alsopossible.

For sheeted buildings it is also necessary to distinguish between:• steel (orother metal) sheeting• fibre reinforced cladding panels• curtain

walling• other forms ofglazing.

8-1



and forbuildings with masonry cladding between:

• masonry which is supported against wind loads by the steelwoit• free-standing masonry• precast concrete units.

and again for supported masonry, between walls with or without damp-proof ourses made of

compressiblematenal.

8.2.2 Roof claddingThe type of oofcladding is also significant and a distinction needs obemade between:

• corrugated orproffled sheeting• felted metal decking orother felted construction• tiled roofs• concrete roof labs.

8.3 Deflectlons ofportal frames8.3.1 Types ofdeflectionUnder gravity oads, he principal deflections of apitched roofportal frame are:

• outward horizontal spread of he eaves• downward vertical movement of the apex.

Under side loads due to wind he frame will sway so that both eaves deflect horizontally in

the samedirection.

Positive and negativewind

pressureon the roofwill also

modifyhe

vertical deflections due to gravity oads.

8.3.2 Loads to be considered

Depending on he circumstances, it may benecessary o consider:

• dead load• imposed oad• all gravity oads (i.e. dead & imposed)• wind oad• wind oad plus dead load• 80% of wind oad plus imposed oad)• 80% of wind plus imposed) plus 100% ofdead load.

Only he imposed oad and the wind oad arc included n the serviceability loads. The deadload need normally only be considered where ts effects arc not already compensated forbythe initial precamber of the frame.

8.3.3 Effects ofcladdingThe cladding tselfoften has the effect of educing he deflection of he frame. It maydo this in three different ways as follows:

• composite action with the frame• "stressed-skint' diaphragm action• independent structural action.

As a result, deflection imits and deflection calculations are normally related to nominaldeflections based on the behaviour ofthe bare steel frame, unless otherwise stated.

The actual deflections are generally less than the nominal values.

8-2



8.4 Behaviour of sheeted buildings8.4.1 ComposIte action

Although composite actionof he sheeting undoubtably reduces deflections in many cases,the effect is very variable due to differences between ypes and proffles of heeting,behaviour of aps, behaviour of ixings, flexibility ofpurlin cleats etc. Data is notwidely available and in some cases the behaviour of he more recent systems with

over-purlin lining, double skin sheeting etc is probably differentIt s normal to ignore this effect n the calculations, but he recommended limits arebased on experience and make some allowance for he difference between nominal andactual deflections.

8.4.2 Stressed-skin actionDesigns taking account of tressed-skin diaphragm action n the strength and stability ofthe structure at the ultimate limit state, should also take advantage of this behaviour n

the calculation ofdeflections at the serviceability limit state.

Where stressed skin action is not aken explicitly into account in the design, it willnevertheless be present n the behaviour of he structure. Neglecting it is apparently onthe safe side, but here is an important exception to this, as follows.

Where significant stressed skin diaphragm action develops due to the geometry of hebuilding, but he fixings of he sheeting are not designed to cope with the resultingforces, the fixings will be over-strained, including localised hole elongation and tearingof he sheeting. To keep this within acceptable limits at the serviceability limit state,differential deflections between adjacent rames have to be limited, otherwise in servicethe sheets may leak at their ixings.

8.4.3 Gable endsSheeted gable ends are generally so stiff, in their own plane, hat their in-planedeflections can be neglected. The result of this is hat it is generally the difference indeflections between he gable end and the next frame which is critical -at east oruniform spacing of rames. However his may be affected by the presence ofbracing, seeFigure 8.1.

This applies both to the horizontal deflection at he eaves and to the vertical deflectionat the ridge.

It should benoted that where sheeted internal division walls are constructed like gableends and not separated from the building envelope, the same relative deflection criteriaapply.

8.5 Behaviour ofbuildings with external walls8.5.1 Free-standing side wailsWhen the side walls are designed ree-standing, to resist the wind loads acting upon themindependently of he frame, he only requirement is to ensure hat, allowing also forconstruction tolerances, the horizontal deflections of he eaves are not such as to closethe gap between he frame and the wall.

The wall should either not contain a horizontal damp-proof ourse, or else have onecomposed ofengineering bricks orother material which is capable ofdeveloping he

necessary flexural esistance (see BS 5628: Part(1):

Clause 18.4.1).



8.5.2 SIde walls supported by steel framesWhen he side walls are designed on the assumption hat they will be supportedhorizontally by the steel frame when resisting wind oads, hen they should be detailedsuch that they can deflect with the frame, generally by using a compressible damp-proofcourse at the base of he wall as ahinge.

The basehinge

should also be taken into account whenverifying

hestability

of the wallpanels (see BS 5628: Part3(: Clauses 18.4.2 and 20.2.3).

8.5.3 Walls and frames sharing load

Ifabase hinge isnot provided, but he side walls ate nevertheless attached o the steelframe, heir horizontal deflections will be equal and both the horizontal and the verticalloading will be shared between he frame and the walls according o their flexuralstiffnesses.

In such cases the walls should be designed in accordance with BS 5628(1) at both theultimate and the serviceability limit states, for all he loading to which hey aresubject.

This procedure is only likely to be viable where either the steel frame is so rigid that itattracts virtually all the load, or the construction of he brick walls is ofacellular ordiaphragm layout, capable of esisting elatively large horizontal forces. In both casesthe design isoutside he scope of hese recommendations.

8.6 Analysis at the serviceability imit state

8.6.1 ServIceabilIty oadsAlthough BS 5950(1) only defines a single level of serviceability loading, this is asimplification.

In the case of he deflection ofa floor beam, eading o cracking ofaplaster ceiling orother brittle finish, it is appropriate o consider he maximum value of he imposed oad,or wind oad, that is anticipated to occur within the design ife of he building, eventhough ts occurrence is rare.

Formany

otherserviceability

conditionsit would be more logical to consider

valuesofimposed and wind oads that occur more frequently, as is envisaged nEurocode (2)•

However or simplicity only the maximum values are considered in BS 5950(1), with thelimiting values adjusted accordingly.

8.6.2 Base flxltyBase fixity is covered in Clause 5.1.2.4 ofBS 5950: Part J(1), which requires useof he same value ofbase stiffness "for all calculations". This clause is ntended to apply to theultimate imit state and the requirement relates o consistency between he assumptionsmade for elastic frame analysis and those applied when checking frame or member stabilityand designing connections.

When accurate values are not available, it permits the assumption ofabase stiffness of10% of he column stiffness for a nominal base, butnot more than the column stiffness fora nominally rigid base.

It is a principle of limit state design hat he verifications of he ultimate and serviceabilitylimit states can be completely independent. At lower load levels, the base stiffness willgenerally be more than at ultimate, particularly for cases where it is as low as 10% atultimate. Further, since BS 5950(1) was drafted, the requirements of he Health and

Safety Executive n relation o erection, have changed he normal detailing ofnominalbase connections from 2 to 4 holding-down bolts.

8-4



Accordingly, it is recommended that abase stiffness of20% of he column stiffness beadopted for nominally connected bases, in analysis at the serviceability limit state.

Similarly, for nominally rigid bases, it is recommended that full fixity be adopted inanalysis at the serviceability limit state, even though Clause 5.1.2.4 requires headoption ofpartial fixity at the ultimate limit state.

8.6.3 PlastIc analysisPlastic analysis scommonly used in he design ofportal frames for the verification ofthe ultimate limit state.

Serviceability loading is less, typically 65-70% ofultimate, and the frame is assumed toremain elastic. Depending on he geometry, his is not necessarily the case under therarely occurring maximum serviceability loads, but for many serviceability criteria hefrequently occurring values are more relevant and the assumption is adequate.

However or such criteria as aportal frame hitting a free-standing masomy wall, or anyother criterion elated to damage to brittle components or finishes, any deformations dueto the formation ofplastic hinges under serviceability loading should also be allowed for.

Such allowance should also be made where the elastic moments under serviceability loadingexceed 1.5

8.7 Building with overhead crane gantriesWhere aportal frame supports gantry girders for overhead ravelling cranes, not only willdeflections be produced in the frames by crane oads, butdefiections of the crane girderswill be produced by wind and gravity oads on the building envelope.

Although vertical deflections may also be produced, the most significant parameter svariation n the horizontal dimension across the crane rack from one rail to the other.

Standard overhead cranes can only tolerate a imited variation n this gauge dimension,whereas with crane brackets added to aotherwise standard pitched roof portal frame herelative horizontal defiections of the two crane girders will be relatively large.

It is therefore aquestion ofdeciding, on the merits ofeach individual case, whether twifi be more cost-effective to have a special crane with greater gauge dimensiontolerances, or whether o design a special stiffer form of frame. Horizontal ies at eaveslevel help reduce spread of he crane rack. Base fixity is also beneficial, especiallywith stepped crane columns. The use ofstepped columns, ather han cantilever rackets,to provide supports for he crane girders, will also reduce deflections, provided that theupper part of he column s not too slender.

Crane manufacturers are often very reluctant oprovide crane gantries with more than avery limited play in he gauge and it is mportant to ascertain what is available at the

earliest possible stage.

In any case, it is advisable to use relatively rigid frames where cranes are carried,otherwise significant horizontal crane forces may be transferred to the cladding. Unlessthe cladding fixings have been designed accordingly, damage o cladding or fixings mayresult.

It s also advisable to limit the differential lateral movements between he columns inadjacent rames, measured atcrane rail level.

8 5



8.8 PondingTo ensure he correct discharge of ainwater from a nominally flat or low-pitched roof,the design of all roofs with a slope of ess than 1 in 20 should be checked o ensure thatrainwater cannot collect in pools.

In this check, due allowance should be made for construction tolerances, fordeflections of

roofing materials,deflections

oftructural

componentsand the

effects ofprecamber andforpossible settlement of oundations.

Precanthering may reduce he possibility ofponding, but only if he rainwater outlets areappropriately located.

Where he roof slope is 1 in 33 or ess, additional checks should be made to ensure hatcollapse cannot occur due o the weight ofwater collected in pools formed by thedeflections of tructural members or roofing materials, ordue to the weight ofwaterretained by snow.

Attention should be paid to deflections ofmembers or roofmg materials spanning at rightangles to the slope as well as those spanning parallel to the roof slope.

8.9 VIsual appearanceDeflection imits based onvisual appearance are highly subjective. As noted in Section 8.6the values under frequently occurring oads are actually relevant, but equivalent valuesunder maximum serviceability loads are used.

The main criterion concerned sverticality of columns, expressed as a imit on lateraldeflection at the eaves. However or rames supporting false ceilings, imits onverticaldeflection at the ridge are also relevant.

8.10 IndicatIve valuesValues for limiting deflections appropriate forpitched roof portal frames without cranes,or other significant loads supported rom the frame, are given in Table 8.1 for a range ofthe more common side and roof cladding materials. In this table, side cladding comprisingbrickwork, hollow concrete blockwork or precast concrete units is assumed to be seated on adamp-proof ayerand supported against wind by the steel frame.

In using this able forhorizontal deflections, the entries forboth the side cladding andthe roof cladding should be inspected and the more onerous adopted. For the verticaldeflection at the ridge two criteria are given; both should be observed.

The values fordifferential deflection relative o adjacent rames apply particularly othe frame nearest each gable end ofabuilding and also to the frames adjacent o anyinternal gables or division walls attached o the external envelope. Note however hatdifferential deflections

maybe reduced

byroof

bracing,see

Figure8.1.

The symbols used in Table 8.1 are defined inFigure 8.1



Table 8.1 Indicative deflection limits forpitched roofsteel portal frames

a. HorIzontal deflection at eaves level-due to unfactored wind load or unfactored imposed roof load or 80%ofunfactored (wind & mposed) loads

Type ofcladding Absolutedeflection

Differentialdeflection relative to

adjacentrame

Side cladding:

Profiled metal sheeting

Fibre einforced sheeting

Brickwork

Hollow concrete blockwork

Precast concrete units

.j.jh

<

—

<'I h2+ b2

'd h2+ b2

"h2÷ b2

Roof cladding:


Fibre reinforced sheeting

Felted metal decking

—

—

— <b. Vertical deflectIon at ridge (for rafter slopes 3°)- due to unfactored imposed roof oad or unfactored wind load or 80%of unfactored (imposed &wind) loads

Type of roof cladding Differential deflection relative toadjacent frame


Fibre einforced sheeting

Felted metal decking:- supported on purlins

-supported on rafter

and s2

b and ' S2

and '1 b22 s2

<j and b 2



— +2/

Bracing

L b L b b b

Maximum deflection

Relative deflections = 6, 6. 63 etc.

Figure 8.1 Portal rame -definitions

8 8

h

I L

1

r

L

62 163



8.11 References1. BRiTISH STANDARDS INSTITUTION

(see Section 19)

2. COMMISSION OF THE EUROPEAN COMMUNITIESEurocode No.3: Design of teel structuresPart 1: General rules and rules for

buildings(Final

draft)Further reading3. DAVIES J.M. and BRYAN E.R.

Manual on stressed skin diaphragm designGranada, 1982

4. BRICK DEVELOPMENT ASSOCIATION/BRITISH STEELBrick cladding to steel framed buildingsBrick Development Association and British Steel Corporation Joint Publication,London, September 1986

5. WOOLCOCK S.T. and KJTIPORNCHAI S.Survey ofdeflection imits for portal frames in AustraliaJournal of Constructional Steel Research Vol 7, No 6, Australia, 1987

6. FISHER, J.M and WEST, M.A.Serviceability design considerations for low-rise buildingsSteel Design Guide Series No 3

American Institute ofSteel Construction, Chicago, 1990



9. ELECTRIC OVERHEAD TRAVELLING CRANESAND DESIGN OF GANTRY GIRDERS

9.1 Crane classification

BS 466(1) and BS 2573(') are the standards which apply to the design ofoverhead ravellingcranes. The structural aspects ofoverhead crane design is covered by BS 2573: Part ](1)

The above standards place overhead ravelling cranes into four loading classes, Qi, Q2, Q3and Q4 according to the frequency with which he safe working load is ifted. Q4 is theheaviest duty. Cranes are further categorized according to their degree of utilization intoone ofnine classes U to U9 inclusive. Cranes in class U9 would be in continuous use withahigh frequency of ifting operations.

9.2 Design of crane gantry girdersFigure 9.1 and Tables 9.1,9.2 and 9.3 give dimensions and static wheel loads of ypicalclass Q2 cranes and these are suitable for preliminary design. For the final design theactual dimensions and static wheel oads must be obtained from the manufacturer of hecrane to be nstalled.

Inadequate design and installation ofgantry girders and rail trackcould effect the smoothrunning and safe operation of he crane. The attention of designers and erectors is drawnto Appendix FofBS 466(1) which gives a comprehensive set ofgeometrical and dimensionaltolerances to which he rail track should be constructed.

9.2.1 Crane loading effects

(i) Ultimate imit states

The relevant factors for the limit state of trength and stability which apply to thedesign ofcrane gantry girders are given in Table 9.4. It should be noted for the verticalloads that he Yf factors are applied o the dynamic crane oads, i.e. the static verticalwheel loads increased by the appropriate allowance fordynamic oads.

(ii) Dynamic and impact effects

For canes of loading class Q3 and Q4 as defined inBS 2573: Part J(1) the dynamic effectvalues for vertical and horizontal surge loading should be established n consultation withthe crane manufacturers.

For other cranes the following allowances should be taken to account forall forces setupby vibration, shock from slipping of lings, kinetic action of acceleration and retardationand impact ofwheel oads.

(a) For vertical loads the maximum static wheel loads should be ncreased by the followingpercentages:

Electric overhead cranes 25%Hand operated cranes 10%

9-1



9-2

0

.9

4I-0;



Table 9.1 Double girder pendant controlled ranes or oading class Q2 o BS 466 and BS2573: Part 1(1)

(See Figure 9.1)

Span A B C D E F H W Crab Crane WheelCapacity S mm mm mm mm mm mm mm mm wt. wt. loadtonnes metres tonnes tonnes tonnes

8 590 920 895 2500 2.52 1.6910 590 970 945 2500 3.41 1.9412 590 1040 1015 2500 4.20 2.15

14 590 1120 1095 3100 5.56 2.4916 590 1120 1095 3700 6.87 2.832 18 590 1120 1095 660 200 260 7900 3700 0.55 7.50 2.98

20 620 1380 1355 3700 8.91 3.3322 620 1380 1355 3700 10.43 3.7124 620 1380 1355 4300 11.23 3.9126 620 1545 1520 4300 12.95 4.34

8 640 970 945 2500 2.96 2.2710 640 1040 1015 2500 3.77 2.5012 640 1120 1095 2500 4.66 2.7314 640 1120 1095 3100 6.22 3.1416 640 1120 1095 3700 6.86 3.32

3 18 640 1135 1110 660 200 260 7300 3700 0.55 9.16 3.8620 670 1380 1355 3700 8.91 3.8222 670 1380 1355 3700 10.43 4.2024 670 1380 1355 4300 11.23 4.4026 670 1545 1520 4300 12.95 4.83

8 700 1070 1045 2500 3.68 3.4410 700 1140 1115 2500 4.65 3.7312 700 1140 1115 2500 5.64 4.0114 700 1140 1115 3100 6.62 4.2816 700 1170 1145 3700 8.85 4.80

5 18 700 1170 1145 760 200 260 9700 3700 0.95 9.69 5.0320 730 1420 1395 3700 9.29 4.93

22 730 1420 1395 3700 10.81 5.3224 730 1420 1395 4300 11.61 5.5526 730 1585 1560 4300 13.33 5.98

8 870 1250 1225 260 2500 4.88 4.9210 870 1250 1225 260 2500 5.84 5.2712 870 1250 1225 260 2500 6.45 5.4914 870 1280 1255 260 3100 8.77 6.0716 870 1280 1255 260 3700 9.57 6.30

7½ 18 870 1350 1325 970 200 260 11250 3700 1.70 11.21 6.7420 900 1510 1485 260 3700 10.01 6.4422 900 1510 1485 260 3700 11.53 6.8224 900 1675 1650 260 4300 13.17 7.28

26 900 1850 1800 430 4300 14.73 7.678 920 1250 1225 2500 5.18 6.19

10 920 1250 1225 2500 5.84 6.4712 920 1278 1255 2500 7.98 6.9814 920 1280 1255 3100 8.82 7.2616 920 1375 1325 3700 10.68 7.77

10 18 920 1375 1325 970 200 430 9700 3700 1.70 11.60 8.0420 950 1535 1485 3700 11.11 7.9122 950 1715 1665 3700 12.67 8.3024 950 1715 1665 4300 13.65 8.6126 950 1865 1815 4300 15.17 8.99

Continued

9-3



Tabi. 9.1 (continued)

(See Figure 9.1)

Span A B C D E F H W Crab Crane WheelCapacity S mm mm mm mm mm mm mm mm wt. wt. loadtonnes metres tonnes tonnes tonnes

8 1420 1370 200 430 3700 6.30 8.7210 1420 1370 200 430 3700 6.93 8.9612 1575 1525 200 430 3700 8.17 9.4414 1575 1525 200 430 3700 9.26 9.8116 1575 1525 200 430 3700 10.58 10.23

15 18 1415 1740 1690 970 200 430 7300 3700 2.40 12.02 10.5920 1740 1690 200 430 3700 12.86 10.8922 1890 1840 200 430 3700 14.34 11.2624 1890 1780 220 500 4300 20.59 13.1526 1890 1780 220 500 4300 21.76 13.48

8 1757 1525 200 430 3700 7.12 11.1610 1575 1525 200 430 3700 7.70 11.4112 1575 1525 200 430 3700 9.02 11.96

14 1740 1690 200 430 3700 10.30 12.4016 1740 1690 200 430 3700 11.14 12.7220 18 1440 1890 1840 970 200 430 6700 3700 2.40 12.50 13.06

20 1890 1780 200 500 3700 18.32 14.9022 1890 1780 220 500 3700 19.48 15.2424 2035 1925 220 520 4300 22.07 15.9326 2035 1925 220 520 4300 23.35 16.29

8 1650 1540 220 500 4300 11.40 14.9010 1650 1540 220 500 4300 11.97 15.0412 1650 1540 220 500 4300 13.14 15.6214 1800 1690 220 500 4300 14.36 16.1316 1800 1690 220 500 4300 15.22 16.49

25 18 1650 1950 1840 1150 220 500 8000 4300 4.00 18.83 17.5220 1950 1840 220 500 4300 20.03 17.9222 2100 1990 220 520 4900 22.54 18.6424 2100 1990 235 600 4900 24.53 19.2026 2125 2035 235 600 4900 27.78 20.08

8 1650 1540 220 500 4300 11.00 17.6510 1650 1540 220 500 4300 12.33 18.2412 1800 1690 220 500 4300 13.49 18.8714 1800 1690 220 500 4300 14.14 19.3716 1950 1840 235 600 4900 18.45 20.57

32 18 1650 1950 1840 1150 235 600 8000 4900 4.00 19.61 21.0020 2100 1990 235 600 4900 21.99 21.71

22 2100 1990 235 600 4900 23.26 22.1424 2210 2035 250 620 4900 26.69 23.0726 2210 2035 250 620 4900 28.11 23.51

(1) Dimension B s based upon construction where end carriages are built ntobridgesmembers for maximum rigidityand compact headroom dimension. Alternative ndconstructions can be provided o either ncrease or educe dimension B to suitexisting building conditions.

(2) The height of ift, H orhookpath dimension, isbased upon a standard rab unit.Alternative crabs are available inallcapacities for extended heights of ift.

(3) Crane weight includes he weightof he crab.

(4) Weights ofcrane and crab are with unloaded ooks.

(5) Wheel loads are forstatic conditions withmaximum working load and minimum crabapproach.

(6) Above nformation is approximate only and s ntended forguidance. Exact nformationshould be obtained from manufacturers' publication.

9-4



Table 9.2 Single hoist cranes for oading class Q2 to BS 466 and BS2573: Part 1(1)

(See Figure 9.2)

Span Crab Crane Wheel WheelsCapacity A B C D E F G H K L wt. wt. load in endtonnes m mm m m m m m m m m tonnes tonnes tonnes carriage

0.8 3.0 4.1 5.0 3.91.0 3.7 4.7 6.5 4.71.1 3.8 4.9 1.76 8.5 5.7 21.3 4.1 5.2 11.0 6.71.4 4.6 5.6 14.0 7.81.4 5.1 6.1 17.5 9.6

6.9 5.68.8 6.3

2.6 11.4 7.4 215.0 8.619.4 9.824.5 11.5

7.5 6.810.0 7.7

2.8 12.9 8.7 217.0 9.821.7 11.527.5 12.7

8.5 8.210.7 9.3

2.8 13.8 10.3 218.0 11.522.8 12.728.8 14.5

9.4 9.811.9 11.0

3.0 15.0 11.8 219.3 13.024.0 14.530.5 16.0

11.0 12.013.6 13.3

4.0 16.6 14.5 221.3 16.026.3 14.532.5 19.5

12.5 15.0

15.0 16.04.5 18.5 17.5 223.0 19.028.0 20.334.0 22.0

(1) Crane weight includes the weightof he crab.

(2) Weights ofcrane and crab are with unloaded hooks.

(3) Wheel loads are forstatic conditions with maximum working load and minimum crab approach.

(4) Above nformation is approximate onlyand is ntended forguidance. Exact nformation should beobtained rom manufacturers' publication.

9-5

10 240 1.612.5 240 1.6

516 250 1.6 0.9 0.8 16 020 250 1.725 270 1.732 270 1.7

10 240 1.7 0.8 3.0 4.112.5 240 1.7 1.0 3.7 4.7

8 16 250 1.7 0.9 0.8 16 0.27 1.1 3.7 4.920 250 1.8 1.3 4.1 5.225 270 1.8 1.4 4.6 5.632 270 1.8 1.5 5.1 6.1

10 250 1.8 0.8 3.0 4.112.5 250 1.8 1.0 3.7 4.7

10 16 270 1.8 1.0 0.8 16 0.3 1.1 3.9 4.920 270 1.9 1.3 4.1 5.225 280 1.9 1.4 4.6 5.632 280 1.9 1.5 5.1 6.1

10 270 2.0 0.8 3.2 4.612.5 270 2.0 1.0 3.8 4.9

12.5 16 280 2.0 1.0 1.0 16 0.3 1.1 4.0 5.020 280 2.1 1.3 4.1 5.225 290 2.1 1.4 4.6 5.832 290 2.1 1.5 5.1 6.2

10 270 2.0 0.8 3.4 4.612.5 270 2.0 1.0 3.8 4.9

16 16 280 2.0 1.1 1.0 16 0.4 1.1 4.0 5.020 280 2.1 1.3 4.1 5.225 290 2.1 1.4 4.6 5.832 290 2.1 1.5 5.1 6.2

10 280 2.1 0.8 3.4 4.612.5 280 2.1 1.0 3.8 4.9

20 16 290 2.1 1.2 1.1 16 0.5 1.1 4.0 5.020 290 2.2 1.3 4.1 5.225 300 2.2 1.4 4.6 5.832 300 2.2 1.5 5.1 6.2

10 290 2.2 0.8 3.4 3.4

12.5 290 2.2 1.0 3.8 3.825 16 300 2.2 1.4 1.1 16 0.6 1.1 4.0 4.020 300 2.2 1.3 4.1 4.125 300 2.3 1.4 4.6 4.632 300 2.3 1.6 5.1 6.2



—-

L

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L+I

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_

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I

K

I

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Fg

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Table 9.3 Double hoist cranes for oading class Q2 o BS 466 and BS 2573: Pafl 1(1)

(See Figure 9.3)

Span Crab Crane Wheel WheelsCapacity A B C D E F G H 1< L M wt. wt. load in endtonnes m mm m m m m m m m m m tonnes tonnes tonnes carriage

10 280 2.112.5 280 2.1

20/5 16 290 2.120 290 2.225 300 2.232 300 2.2

0.8 3.51.0 3.8

0.5 1.1 4.01.3 4.11.4 4.61.6 5.1

(1) Crane weight includes he weight of he crab.

(2) Weights ofcrane and crab are with unloaded ooks.

(3) Wheel oads are for static conditions withmaximum working load and minimum crab approach.(4) Above nformation is approximate only and s ntended forguidance. Exact nformation

should be obtained frommanufacturers' publication.

9-7

0.2 1.7 16

4.64.95.05.25.86.2

0.81.01.11.31.41.6

4.0 5.04.2 5.24.3 5.34.4 5.54.6 5.85.1 6.2

0.8 4.0 5.0

1.0 4.2 5.21.1 4.3 5.31.3 4.4 5.51.4 4.6 5.81.6 5.1 6.4

10 300 2.312.5 300 2.3

25/5 16 300 2.420 300 2.425 300 2.432 300 2.4

10 320 2.5

12.5 320 2.532/5 16 320 2.5

20 330 2.625 330 2.632 330 2.6

10 320 2.512.5 320 2.5

40/10 16 320 2.520 330 2.625 330 2.632 330 2.6

10 330 2.612.5 330 2.6

50/10 16 330 2.620 340 2.725 340 2.732 340 2.7

10 380 3.012.5 380 3.0

63/10 16 380 3.020 380 3.025 380 3.032 380 3.0

1.4 1.8 16 0.5

1.4 1.9 16 0.5

1.4 1.9 16 0.6

1.5 2.0 16 0.6

1.7 2.1 16 0.6

0.8 8.0

0.9 12

1.0 14

1.1 15

1.1 20

1.1 25

12.516.017.523.028.036.0

15.018.022.026.532.541.0

17.0

20.024.028.535.043.0

18.522.026.030.537.045.0

21.035.030.035.041.050.0

28.033.038.044.051.060.0

0.8 4.21.0 4.41.1 4.51.3 4.71.4 4.81.6 5.1

13.014.0

15.517.018.520.0

20.022.023.525.027.030.0

24.0

25.027.028.530.533.0

24.026.027.830.032.034.5

30.032.034.237.040.043.0

36.038.042.045.023.926.0

5.35.55.65.76.06.4

2

2

2

2

2

222244

0.81.01.11.31.41.6

4.3 5.54.6 5.84.7 5.94.9 6.15.0 6.25.2 6.4

0.8 4.6 5.81.0 4.7 5.91.1 4.9 6.11.3 5.0 6.21.4 5.1 6.21.6 5.2 6.4



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(b) The horizontal surge force acting transverse to the rails should be taken as apercentage of the combined weight of he crab and load lifted as follows:

For electric overhead cranes 10%For hand operated cranes 5%

(c) Longitudinal horizontal forces acting along the rails should be taken as apercentage

of he static wheel loads which can occur on the rails as follows:

For overhead cranes eitherelectric or hand operated 5%

TabI. 9.4 Crane oading effects

Loading Factory

Vertical loadVertical load acting withhorizontal loads(crabbing or surge)Horizontal loadHorizontal load acting with vertical

*Crane load acting with wind oad

1.6

1.41.61.41.2

*When considering windor mposed load and crane oadingacting together, the value of for dead oad may betaken as 1.2

(iii) Crabbingof

mlleyGantry girders ntended to carry cranes of oading class Qi and Q2 as defined inBS 2573: Part J(1) need notbe designed for the effects ofcrabbing action.

Gantry girders ntended to carry cranes ofclass Q3 and Q4 as defined inBS 2573: Part 1(1)

should be designed for the following couple due to the crabbing action of wo wheels orbogies comprising two equal and opposite forces, FR, acting ransverse to the rail, one ateach end of he wheelbase.

LW W

FR=4' but -where L is the span of he crane

W is the factored maximum load on awheel or bogie pivotis the distance between the centres of he two end wheels orbetween he pivots of he bogies (where horizontal guide rails are used as the wheelbase of he guide rails).

(iv) Wind loading onoutdoor gantries

The wind loads on the gantry girders and supporting structures in the case of outdoorgantries are obtained fmm:

(a) BS 2573: Part J(1) forcranes in working condition.(b) CP3: Chapter V: Part (1) forcranes which are not working.



(v) Deflection limits for gantry girders

Vertical deflection due ounfactored static wheel oads 600

Horizontal deflection due tounfactored crane surge 500(Calculated on the top flange assemblyproperties alone)

(vi) Failure

Only hose gantry girders and supporting tructures ofcranes ofutilization classes U7 toU9 as defined in BS 2573(1) are required o be checked for fatigue by reference to the fatiguedesign clauses of hat standard.

9.2.2 DesIgn notes

The top flange ofcrane gantry girders are nomially einforced with channel sections orplates in order to resist the horizontal loads.

These gantry girders are usually designed on the basis that the vertical load effects areresisted by the combined section and he horizontal loads are resisted by the top flangeassembly only; the horizontal loads being deemed to act at the centroidal axis of he topflange assembly. Further, notwithstanding that he horizontal loads are applied at raillevel, the torsional effects on the gantry girder are ignored.

Gantry girders can be simply supported orcontinuous. The deflections ofcontinuous

girders are much reduced as compared with simply supported.

For many situations gantry girder will be fabricated using Universal Beams but for highcapacity crane oadings welded plate girders may be required. When designing plate girdersattention must be given to Clauses 4.11.4 and 4.11.6 ofBS 5950: Part (1)•

Additional provisions or gantry girders, Clause 4.11 ofBS 5950: Part J(l) requiresthat in addition to the fulfilling the general rules for beams, gantry girders should becapable of resisting the local compression under he wheel.

(i) Local compression under wheels

Local compression on the web may be obtained by distributing the crane wheel load over alength XR where:

XR = 2(HR +7')

where HR is he rail height;T is he flange hickness.

Alternatively where he properties of he rail are known:

XR= KR[if

÷

1R]where t is he web thickness

i is he second moment of area of he flange about its horizontal centroidalaxis

9-10



is the second moment of he area of he crane rail about its horizontalcentroidal axis

KR is a constant aken as:

(a) when he crane rail is mounted directly on the beam flange KR = 3.25(b) where a suitable resilient pad not ess than 5 mm thick is nterposed

between he crane rail and he beam flange KR = 4.0.

The stress obtained by dispersing the oad over this length should not be greater thanp(the design strength of he web).

(ii) Lateral torsional buckling

In the case of ateral orsional buckling no account should be taken of he effect ofmomentgradient, i.e. n and m should be taken as 1.0 (see Clause 4.3 ofBS 5950: Part 1(1)).

(iii)Universal beam top flange reinforcement

It is recommended thatonly plates 10 mm thick shall be used to act as top flangereinforcement for universal beam gantry girders. Plates < 10 mm thick tend to bend in thetransverse direction on welding. For example plates 10 mm, 12 mm and 15 mm thick by 250 mmor 300 mm wide are suitable for UB serial sizes 457 x 152,457 x 191, 533 x 210 and610 x229.

(iv) Gantry girder support structures

The gantry girder support structures and fixings must be designed taking into account hatthe horizontal forces defined in Sections 9.2.1 (ii) and (iv) above act at the level of herails.

9.3 Design and detailing of crane rail trackThe transverse orizontal oads defined in Sections 9.2.1 (ii) and (iv) above must be takeninto account n considering the lateral rigidity of he rails and their fastenings.

The main functions of ail fixing bolts orclips are to prevent overturning and lateraldisplacement of he rail and by adequately holding down the rail to prevent he formationof a "bow wave" ahead of the crane wheeL Fixing systems should permit easy realignmentand replacement of rails. However, the adjusiment allowed should be limited (say 5 mm eachway) so as to avoid large eccentric vertical loading on the girder.

Any further movement should be obtained by adjusting he girder on the column cap. The useof ixings hat permit "longitudinal float" of the rail should cater for he relativemovement between he rail and the top flange ofa simply supported girder due to theshortening of he flange under load.

For his situation fully continuous rails have to be used. Continuous rails are obtainedby using bolted fish plate splices with the rail ends closely butted or by site welding in

the case of ails for heavy duty cranes. Site welding of crane rails is a highlyspecialized technique.

A major advantage of continuous rails is he avoidance of he discontinuities at the jointswith the accompanying wheel flange and rail wear and loosening of ixings.

If he rails or simply supported girders are not fully continuous as described above thenit is recommended that the rail lengths are the same as the girders and the joints coincidewith the gantry girder oints.

9-11



It is again emphasized that the safe operation of he crane depends upon the rail trackbeing designed or and erected o the comprehensive set ofdimensional and geometricaltolerances given in Appendix F ofBS 466(1).

There is a wide range ofproprietary rail fixings available and the manufacturersliterature should be consulted before fmalizing design details.

Details ofavailable crane rails are given in Section 16.

9.4 Gantry girder end stopsThe end stops must be designed to withstand the impact of he crane ravelling at fullspeed. Typical stops are shown inFigure 9.4.

Weldedplate

endstop.

ir11.I T T

.

01Umn

Ior H section end stop.

1L

Column

FIgure 9.4 Gantry girder end stops

9.5 References1. BRITISH STANDARD INSTITUTION

(see Section 19)

A VVIll lU UI

The information in Tables 9.1 to 9.3 was obtained from "The Sections Book" which isproduced by British Steel General Steels - Sections in association with British Constructional Steelwork

Association.

9-12



10. FASTENERS

Fasteners used in structural steciwork will conform to one of he following standards (seeSection 19):

Bolts:

BS 4190: 1967 Iso Metric black hexagon bolts, screws and nuts

BS 4933: 1973 ISO Metric black cup and countersunk head bolts and screws withhexagonal nuts

BS 3692: 1967 ISO Metric precision hexagon bolts, screws and nuts

BS 4395: High strength friction grip bolts and associated nuts and washers

Part 1: 1969 General gradePart2:1969 Highgrade

Washers:

BS 4320: 1968 Metal washers for general engineering purposes metric series (washersfor HSFG bolts are included in BS 4395(1)).

10.1 Mechanical properties and dimensionsDetails of he mechanical properties, dimensions and mass for he range ofbolts, both insize and strength grade, that are normally used in structural steelwork are given in theTables 10.1 to 10.11. For details ofbolts outside his range and for fuller nformation,the original British Standards hould be consulted.

Note that the term "black" in the case ofbolts does not refer to the colour but mpliesthe comparative wider tolerances to which hese bolts are normally manufactured.

10.2 Strength grade classificationThe SO (International Organisation of Standardisation) system of trength grading has beenadapted n the above British Standards. In the ISO System the strength grade for bolts isgiven by two figures separated by apoint. The first figure is one tenth of he minimumultimate stress in kgf/mm2 and the second igure is one tenth of the percentage of theratio ofminimum yield stress to minimum ultimate stress.

The single grade number for nuts indicates one enth of he proof oad stress as kgl7mm2and

correspondswith the bolt ultimate stress to which it is matched

e.g.an 8

gradenut s

used with an 8.8 grade bolt. It s permissible to use ahigher strength grade nut han thematching bolt number. Grade 10.9 bolts are suggested with grade 12 nuts since there is nograde 10 nut in the BS series.

To minimise the risk of hread stripping at high loads, BS 4395(1) high strengthfriction grip bolts are matched with nuts one class higher than the bolt.



Table 10.1 Mechanicalproperties and dimensions forgrade 4.6black bolts and nuts to BS 4190 andgrade 8.8bolts and nuts toBS 3692

ISOMetric coarse threads

M12 M16 M20 (M22) M24 (M27) M30 (M33) M36

Pitch (mm)

Tensile stress area (mm2)

Basic effective diameter(Pitch diameter) (mm)

1.74 2.00 2.50 2.50 3.00 3.00 3.50 3.50 4.00

84.3 157 245 303 353 459 561 694 817

10.863 14.701 18.376 20.376 22.051 25.051 27.727 30.727 33.402

Grade 4.6 Ultimate load kNProof load kN

Grade 8.8 Ultimate load kNProof load kN

33.118.766.248.1

61.634.812389.6

96.154.3192140

118.867.3238173

13878.2277201

180102360262

220124439321

272154544396

321181641466

Length of hreadsBS4190 (Uptoandinc.125mmand (Over 125mm up to and

(inc.200mmBS3692 (Over200mmBS 4190 (Up o and inc. 125mm(Short thread ength)

30

3649-

38

445724

46

526530

50

566933

54

607336

60

667940

66

7285-

72

7891

-

78

8497-

Dimensions (mm)Maximum width across flatsMaximumwidthacrosscornersNominal head depth ofboltsNominal depth of nuts

19.021.98.010.0

24.027.710.013.0

30.034.613.016.0

32.036.914.018.0

36.041.615.019.0

41.047.317.022.0

46.053.119.024.0

50.057.722.026.0

55.063.523.029.0

BS4190 BOLT BS3692 BS4190 NUT BS3692

Table 10.2 Manufacturers recommended range forblack hexagon bolts and screws to BS 4190 grade 4.6metric coarse hread

Thread lengths for BS4190 (and BS3692) boltsNominalbolt length Standard hread length Short hread ength

Up to and nc. 125mmOver 125, up to and nc. 200 mmOver200 mm

2d ÷ 6mm2d + 12 mm2d ÷ 25mm

1.5d--

d nominalboltdiameter

Hexagon head bolts and nuts -standard and short hread engths, mm

DiameterLength (mm)

—25 30 35 40 45 50 55 60 65 70 75 80 90 100 110 120 130 140 150 160 180 220 260 300

M12M16M20M24

X X0

X0

X00

X00

XX00

XX00

XX0XC0

XXCXC

XXCXCX0

XX0X0

XX0X0X0

XX0X0X0

XXCXCXC

XXXX

XXXX

XX

XXXX

X

XXXX

XXXX

XXXX

XXXX

XXXX

X— Standard thread engths0 — hort hread engths

10-2

Continued...

Sizes shown inbrackets are non-preferred.



Sizes shown nbrackets are non-preferred.

10-3

Table 10.2 (Continued)Hexagon head screws

DiameterLength mm)

25 30 35 40 45 50 60 70 80 90—100

M12 X X X X X X X X X X X

M16 X X X X X X X X X X

M20 XXXXXXX X

X Standard thread engths

Table 10.3 Dimensions forblack washers to BS 4320

Alldimensions in mm

I

Nom.BoltDia.

Inside diameter, d1 Outside diameter, d2 Thickness, S

Nom. Max. Mm. Nom. Max.Mi Nom. Max. Mm.

Normal diameter Form E)

M6M8M10M12M16M20

(M22)M24

(M27)M30

(M33)M36

6.6 7.0 6.69.0 9.4 9.0

11.0 11.5 11.014 14.5 1418 18.5 1822 22.6 2224 24.6 2426 26.6 2630 30.6 3033 33.8 3336 36.8 3639 39.8 39

12.5 12.5 11.717 17 16.221 21 20.224 24 23.230 30 29.237 37 35.839 39 37.844 44 42.850 50 48.856 56 54.560 60 58.566 66 64.5

1.6 1.9 1.31.6 1.9 1.32.0 2.3 1.72.5 2.8 2.23 3.6 2.43 3.6 2.43 3.6 2.44 4.6 3.44 4.6 3.4

4 4.6 3.45 6.0 4.05 6.0 4.0

Large diameter (Form F)

M8M10M12M16M20

(M22)M24

(M27)M30

(M33)M36

9 9.4 911 11.5 1114 14.5 1418 18.5 1822 22.6 2224 24.6 2426 26.6

2530 30.6 3033 33.8 3336 36.8 3639 39.8 39

21 21 20.224 24 23.228 28 27.234 34 32.839 39 37.844 44 42.8

50 50 48.856 56 54.560 60 58.566 66 64.572 72 70.5

1.6 1.9 1.32 2.3 1.72.5 2.8 2.23 3.6 2.43 3.6 2.43 3.6 2.4

4 4.6 3.44 4.6 3.44 4.6 3.45 6.0 4.05 6.0 4.0

Extra large diameter Form G)

M6M8M10M12M16M20

(M22)M24

(M27)M30

(M33)M36

6.6 7.0 6.69 9.4 9.0

11 11.5 11.014 14.5 14.018 18.5 18

22 22.6 2224 24.6 2426 26.6 2630 30.6 3033 33.8 3336 36.8 3639 39.8 39

18 18 17.224 24 23.230 30 29.236 36 34.848 48 46.860 60 58.566 66 64.572 72 70.581 81 7990 90 8899 99 97108 108 106

2 2.3 1.72 2.3 1.72.5 2.8 2.23 3.6 2.44 4.6 3.45 6.0 45 6.0 46 7 56 7 58 9.2 6.88 9.2 6.810 11.2 8.8



Table 10.4 Approximate mass n kgper 1000 orblack bolts and nuts o BS 4190

Lengthunder head Diameter ofbolt n mm

mm 6 8 10 12 16 20 (22) 24 (27) 30 (33) 36

2530

3540

8.97 18.7 36.6 52.510.1 20.7 39.1 56.1 113

11.2 22.7 42.2 59.7 12112.3 24.7 45.3 64.1 129 214

45505560

13.4 26.7 48.4 68.5 137 22714.5 28.7 51.5 72.9 144 239 294 37715.6 30.7 54.6 77.3 153 251 309 39516.7 32.7 57.7 81.7 160 264 324 412

65707580

17.8 34.7 60.8 86.1 168 276 339 42918.9 36.7 63.9 90.5 176 288 354 44720.0 38.7 67.0 95.0 184 300 369 46421.1 40.7 70.1 100 192 313 384 481

621643666

90100110120

44.7 76.3 109 207 337 414 51648.7 82.5 118 223 362 444 55088.7 127 239 387 474 58594.9 136 255 411 504 620

710755800845

93098610421098

1162122912951362

137114511531

130140150160

101 145 270 436 534 654107 154 286 460 564 689113 163 302 485 594 723119 172 758

890935980

1025

1154121012661322

1429149515621628

1610169017701850

170180190200

125 181131 190137 19914.3 208

1070 137814341490

169517621828

1930200920892169

Extra per10 mm 2.22 3.95 6.17 8.88 15.7 24.6 30.0 34.6 44.9 56.0 66.6 79.8

Approximatemass ofnuts

2.32 4.82 10.9 15.9 32.9 59.8 74.4 104 157 209 279 352

Masses nclude one nutper boltbutmake no allowance or washersSizes shown inbrackets are non-preferred.

Table 10.5 Approximate mass n kgper 1000 forblack washers to BS 4320

Type ofwasher

Diameter of bolt in mm

6 8 10 12 16 20 (22) 24 (27) 30 (33) 36

FlatForm E 1.1 2.1 4.0 5.9 11 17 18 32 40 50 71 87

FlatForm F 3.5 5.6 9.1 16 20 26 45 55 60 95 112

Sizes shown n brackets are non-preferred.Because of hickness tolerances, mass may var, by as much as 30%.

10-4



TabI. 10.6 Mechanical roperties orhigh strength rictiongrip bolts and nuts toBS 4395

Bolts - General grade Part 1

Nominal Tensile Proof load Yield Ultimatediameter stress minimum load load

area (Mm. shank (minimum) (minimum)tension)

mm mm2 kN kN kN

(M12) 84.3 49.4 53.3 69.6M16 157 92.1 99.7 130M20 245 144 155 203M22 303 177 192 250M24 353 207 225 292M27 459 234 259 333M30 561 286 313 406M36 817 418 445 591

Minimum elongation after racture or alldiameters is 12% on the test specimen describedin Appendix BofBS 4395: Part 1.

Size shown in brackets s non-preferred. Only obe used for he lighter ype ofconstruction where practical onditions, such as material hickness, do not warrant theusage ofa arger size bolt than M12.

Bolts- Highergrade Part 2

Nominal Tensile Proof load 0.85 of 1.15 of Yield Ultimatediameter stress minimum Proof oad Proof oad load load

area (Mm shank (Maxshank minimum minimumtension) tension)

mm mm2 kN kN kN kN kN

M16 157 122.2 103.9 140.5 138.7 154.1M20 245 190.4 161.8 219.0 216 240M22 303 235.5 200.2 270.8 266 269.5M24 353 274.6 233.4 316 312 346M27 459 356 303 409 406 450M30 561 435 370 500 495 550M33 694 540 459 621 612 680

Minimum elongation after racture ora/Idiameters is 9% on he test specimen described nAppendix BofBS 4395: Part 2.

Nuts

Proof oad

Nominal size General grade Higher gradeof nut Parti Part2

mm kN kN

(M12) 84.3 -M16 157 184.4M20 245 288.4M22 303 356.9M24 353 415.4M27 459 540.0M30 561 660.0M33 - 817.0M36 817 -

Size shown in brackets isnon-preferred.



Table 10.7 Dimensions for high strength riction grip bolts and nuts to BS 4395 Parts 1 and 2See Figure 10.1 for the definition ofdimensions shown in the table

Nominaldiameter

Diameter ofunthreadedshank

B

Pitch(coarsepitchseries)

Widthacrossflats

A

Depthofwasheiface

C

Thicknessofhexagonhead

F

'Dia.of Csk.head

J

Diameterofwasherface

G

DepthofCsk.flash

H

Thicknessof nuts

E

Addition ogrip engthto givelength ofboltrequired"

mm

Max.

mm

Mi

mm mm

Max.

mm

Mm.

mm mm

Max.

mm

Mm.

mm mm

Max.

mm

Mi

mm mm

Max.

mm

Mm.

mm mm

(M12)M16M20M22M24M27M30M33M36

12.7016.7020.8422.8424.8427.8430.8434.0037.00

11.3015.3019.1621.1623.1626.1629.1632.0035.00

1.752.02.52.53.03.03.53.54.0

222732364146505560

21.1626.1631.0035.0040.0045.0049.0053.8058.80

0.40.40.40.40.50.50.50.50.5

8.4510.4513.9014.9015.9017.9020.0522.0524.05

7.559.55

12.1013.1014.1016.1017.9519.9521.95

243240444854606672

222732364146505560

19.9124.9129.7533.7538.7543.7547.7552.5557.75

2.02.03.03.04.04.04.55.05.0

11.5515.5518.5519.6522.6524.6526.6529.6531.80

10.4514.4517.4518.3521.3523.3525.3528.3530.20

2226303436394245

48Size shown in brackets is non-preferred.'Countersunk head."Allows or nut, one flatround washer and sufficient thread protrusion beyond nut.

Thread lengths

Nominal length of bolt

Length of hread

BS4395Parti

BS4395Part2

Upto and including 125mm

Over 125 mm upto andincluding 200 mm

Over 200 mm

2d +6mm

2d + 12 mm

2d +25 mm

2d +12mm

2d + 18 mm

2d + 30 mm

d = hread diameter .e. nominalboltdiameter.

10-6



HEXAGON HEAD

C

B 1IJTJJGrip ength LI

F Length

COUNTERSUNK HEAD

General grade Pt 1

countersunk head

Higher grade Pt 2countersunk head

THE SYMBOL M MAY BE USED AS AN ALTERNATIVE TO 1SOM ON BOLT HEADS

FIgure 10.1 High strength rictiongripbolts and nuts

General grade

-—I

Higher gradePt 2

C

Seneral grade Higher grade

Ptl Pt2



Table 10.8 FIat round washers for use with high strength rictiongripbolts

4Nominalsize

Inside diameterB(mm)

Outside diameterC(mm)

ThicknessA(mm)

*D(mm)

Maximum Minimum Maximum Minimum Maximum Minimum

(M12)M16M20M22M24M27M30M33M36

13.817.821.523.426.429.432.835.838.8

13.417.421.123.026.029.032.435.438.4

303744505660667585

29364348.554.558.564.573.583.5

2.83.43.74.24.24.24.24.64.6

2.43.03.33.83.83.83.84.24.2

11.51417.5192122.5262932

The symbol Mappears on the face ofallMetricSeries washers.

When required washers cloped to this dimension.Sizes shown inbrackets are non-preferred.

Table 10.9 Square taper washers oruse with high strength rictiongrip bolts

Section A-A

All chamfers 45°

Nominalsize

Inside diameterB(mm)

Overallsize C

Mean thickness A

3°and 50 Taper(mm)

8°Taper(mm)aximum Minimum

mm)

(M12)M16M20M22M24M27M30M33M36

14.218.221.923.826.829.833.236.239.2

13.417.421.123.026.029.032.435.438.4

31.7538.1038.1044.4557.1557.1557.1557.1557.15

4.764.764.764.764.764.764.764.764.76

6.356.356.356.356.356.356.356.356.35

The symbol Mappears on he face ofallMetricSeries washers.

Size shown n brackets is non-preferred.

10-8



Table 10.10 Approximate mass n kgper 1000 forHSFG bofts and nuts to BS 4395: Part 1, Part 2

Lengthunder head Diameter ofbolt n mm

mm (12) 16 20 22 24 27 30 33 36

30354045

70 13674 14479 152 24882 160 260

50556065

87 168 272 360 49191 176 285 375 50995 184 297 389 527

100 192 310 404 545

70758085

104 199 322 419 562207 334 434 580 756215 346 449 598 779223 359 464 615 801 1022 1337

90100110120

231 371 479 633 824 1050 1371508 669 869 1106 1393 1791

704 914 1161 1415 1871739 958 1217 1572 1950

130140150160

999 1269 1635 20241045 1325 1702 21041089 1380 1769 2184

1436 1836 2264

170180190200

1491 1903 23431970 2423

25032583

Extra per10mm 8.88 15.7 24.6 30.0 35.6 44.9 56.0 67.1 79.8

Approximatemass ofnuts 26.4 50.7 83.0 112 174.1 242 287 409.8 525

Masses nclude one nutper boltbutmake no allowance or washers.Size shown in brackets s non-preferred.

Table 10.11 Approximate mass n kgper 1000 forHSFG washers to BS 4395:Part 1

Type ofwasher

Diameter of bolt in mm

(12) 16 20 22 24 27 30 33 36

Flat round

Squaretaper3° and 5°

Squaretaper 8°

12.5 22.0 32.8 46.0 60.0 66.6 76.6 96.6 133.3

32 51 41 58 102 97 90 - 78

43 68 54 78 136 129 121 - 104

Size shown in brackets is non-preferred.

10-9



10.3 Protective coatingsWhen required, bolts, nuts and washers should be spun galvanised, sherardised orelectro-plated with zinc or cadmium.

Note that electro-plated finishes may not provide he same degree of protection as metalsprayed orgalvanised teelwork.

10.4 Minimum length ofboltsThe length of he bolt must be such that at least one thread shows above the nut aftertightening, and at least one thread plus the thread runout is clear between he nut andthe unthreaded hank of the bolt.

10.5 Designation ofboltsWhen designating SO Metric bolts, screws ornuts the following information should be

given.(i) General product description, e.g. high tensile orblack, head shape, bolts, screws or

nuts, as appropriate.

(ii) The letter "M" before the nominal hread diameter n mm.

(iii) The nominal length in mm, ifapplicable.

(iv) The appropriate British Standard, e.g. BS3692(1).

(v) The strength grade symbol.

(vi) Details of he protective coating.

Examples

(a) Black hexagon head bolts 16 mm diameter, 70 mm long, strength grade 4.6, galvanised,would be designated:

Blackhexagon

head boltsM16 x 70 to BS 4190, grade 4.6, galvanised o BS 729(1).

(b) Hexagon head bolts 24 mm diameter, 90 mm long, strength grade 8.8, zinc plated withcoating of intermediate thickness, would be designated:

High ensile hexagon head bolts M24 x 90 to BS 3692, grade 8.8, zinc-plated toBS 1706(1).


(see Section 19)

10-10



11. WELDING PROCESSES AND CONSUMABLES

Abrief description s given below of he various welding processes ollowed by a review ofthe requirements, classification and purchasing of he welding consumables. Furtherinformation can be found in Sc! publication, ntroduction o the welding of tructural

steelworkf1).

11.1 Basic requirementsThe process and/or consumables must:

(a) supply heat to effect fusion of he parts to bejoined

(b) make a oint such that the properties of the join are adequate to cater for the designload and fracture toughness requirements; this necessarily includes atisfactory

metallurgical properties(c) enable the process to be made efficiently in any required position; both vertical and

overhead welds may be made by some processes but not all.

11.2 Manual metal-arc (MMA) weldingThis process, s the name suggests, is a manual operation and is solely dependent on heskill of the operator. It is he oldest of all he processes and is widely used by allfabricators.

The electrode consists of acore wire with a flux extruded around it (Figure 11.1). Theflux can consist of ngredients such as cellulose, silicates, titanium, ronoxides,manganese oxides, calcium carbonate, flouride, etc. These constituents are made nto astiffpaste with a sodium silicate binder forextrusion around he core wire; the fluxshould perform several functions when it is melted in the arc, viz:

(a) stabilise the arc

(b) provide he arc and molten weld pool with a gaseous envelope to prevent he pick-up of

oxygenand

nitrogenrom the

atmosphere- such contaminants would

producea weld of

inferior mechanical and metallurgical properties

(c) produce aslag over the hot deposited weld bead to protect it from the atmosphere

(d) produce aslag o form the acceptable weld bead shapes in the welding position flat,horizontal, vertical, overhead) required with adequate slag detachability

(e) add alloys where necessary to the weld metal

(IT) provide henecessary slag/weldmetal reactions

(g) control he deposition rate.

11—1



Core wire

Figure 11.1 Manualmetal-arc welding (MMA)

11.3 Submerged arc (SA) weldingThis is an automatic welding process in which acontinuous bare wire (electrode) is fedfrom a drum through awelding nozzle nto abed ofgranulated flux automatically dispensedalong the joint o be welded. This is shown schematically in Figure 11.2. The heat of hearc melts some of he flux and, as in the manual metal-arc process, provides agaseousenvelope around he arc. The fused flux forms a cover o the deposited molten metal whichprevents oxidation, orother contamination from the almosphere.

Drivemotor To lux

hopper

Weldingnozzle

I lux

• •• Unfused surplus flux

________• Fused flux

\ \\ cJ//// /i//

FIgure 11.2 Submerged arc welding (SA)

11-2

Metal and moltenflux droplets

Fused

WeIdingCurrent

Bare wire

Electrodefeed rollers

electrode

Welding current n



The arc being completely enclosed by flux, spatter and radiation osses are minimal andhigh welding currents can be employed esulting n deep penetration welds. The consequenthigh heat inputs ogether with the fluid type molten flux, produce weld beads of moothsurface appearance.

Fluxes are of hree main types, fused, bonded (agglomerated) and mechanically mixed. Theyconsist of mixtures of various forms of silicon, metal oxides and arc stabilisers. Theparticular make-up can decide deposition rates, slag detachability, necessary cleanliness

ofthe plate surface and weld metal non-metallic nclusions. The latter has a significanteffect on weld metal fracture oughness and in general, the more basic the flux, the fewerthe inclusions in the weld metal.

The electrode wire can also have alloying elements added to it which ransfer o the weldmetal when it is deposited.

The fact that high input currents can be employed means that thisprocess is capable ofhigh deposition ates. Even higher rates can be achieved by the use ofmultiple arcs forwhich wo or hree electrodes operating from suitable power sources are fed into the same

joint. It should be noted, however, that the high heat input will naturally result in adecreased rate ofcooling of he weld metal which, because of ts resultant metallurgicalmicrostructure, can suffer a reduction in fracture oughness.

11.4 Gas metal arc welding (GMA)In this process a small diameter olid electrode scontinuously fed nto the weld with thearc and molten weld pool shielded by agas which prevents he pick upofoxygen andnitrogen rom the atmosphere. Welding with an inert gas, helium or argon is not suitablefor the welding of steel since they form an irregular weld pool but he addition ofoxygen

or carbon dioxide to argon achieves amore stable arc with improved bead shape, betterpenetration and reduced undercut. To counter he effect ofoxygen from the above addedgases in the weld metal, deoxidants are added to the electrode iller wire. As more carbondioxide s added (commonly up to 20 per cent) to the argon, he mode ofmetal transfer fromthe electrode changes rom a spray ype to a globular one. This is very evident when theshielding gas is entirely carbon dioxide, where the globules occasionally hort circuit thearc; spatter increases and the arc sounds harsher.

Gas terminology isnot exact. The term MIG welding metal inertgas welding) shouldstrictly apply to the inert gases only, such as helium and argon. The additions ofoxygen

and carbon dioxide i.e. active gases, to argon is sometimes known as MAG (metal activegas), but in some quarters it is still termed as MIG. When carbon dioxide only isused asa shielding gas the expression MAG (C02) is sometimes employed.

The electrode is fed by means of a speed controlled motor through he nozzle or gun and hegas through he gun orifice (Figure 11.3).

11.5 Gas shielded flux-cored arc welding FCAW)In this process, which can be either semi-automatic or automatic, the electrode contains a

flux within its periphery .e. a flux cored wire. The flux contains arc stabilisers,deoxidants and alloying elements, and as in the previous section, gases are used as ashielding medium. The addition of he flux offers better deoxidation of the weld metalwith improved chemical composition and hence better physical properties particularly notchtoughness. Basic fluxes give low hydrogen weld deposits with good impact values andsubsequent improved resistance to cracking. Small diameter wires, typically 1.2 mmdiameter, are used for all positional welding and diameters 2.0 mm to 2.4 mm for highdownhand depositions increased by the additions of ron powder to the flux. Shieldinggases used are CO2 and Ar/CO2 mixtures.

11-3



Figure 11.3 Gas shielded metal arc welding (MAG)

11.5.1 Self shielded flux-cored arc weldingIn this process no shielding gas is required since the cored flux contains constituentswhich vaporize in the arc to prevent the pick-up ofoxygen and nitrogen by the weld metal.The flux provides good fusion properties and a

quickfreezing slag permits positional

welding and without an external shielding gas the welding equipment is less bulkypermitting easy access to all plate preparations. Welding is unaffected by windy siteconditions since no external gas shroud is employed. Low hydrogen content wires areavailable as with FCAW consumables. Fast depositions are possible in he flat positionsbut care is necessary to employ optimum welding conditions with respect to arc voltage andelectrode feed rate.

11.6 Consumable guide electroslag welding (ESW)

The process originated in Russia and consists of eeding acontinuous bare wire electrodethrough a flux coated metal guide tube centred between he vertical plates being welded.The edges of he plate are square, requiring no preparation which is necessary for weldingthick plates by other processes. The consumable guide isheld in a clamp situated on asmall platform fixed above the weld gap which also holds he feed motor and reel containingthe electrode. Both sides of the weld aperture are enclosed by two full-length watercooled copper shoes to contain he weld metal (Figure 11.4). The arc is nitiated undersome flux on the start plate and when he flux melts it becomes electrically conductive andafter certain equilibrium conditions are achieved, the arc is extinguished. The electrodeis then melted off

byresistance

heating produced bythe

welding currentin

the wire and

Co2gas

tube

Gasshroud-



also the molten slag. To prevent contact with the plates, he guide tube is nsulated withan extruded lux around it and is melted offby the heat of the molten slag and thus addedto the weld metal and slag pools. Very little flux is consumed by the process althoughduring he operation tmay become necessary to add a little flux to the slag. Up to 4 mmdiameter electrode wires are popularly used with alloying additions to obtain mechanicalproperties in the weld metal. Oscillation as shown in the figure may be applied and morethan one electrode and guide employed, enabling hicknesses in excess of400 mm to be

welded. The welding scontinuous with ahigh heat nput and slow cooling rate and isvirtually a casting process with a coarse grain structure near the fusion ine boundary andin he heat affected zone resulting n a low notch toughness n these areas; this can beimproved by apost-weld normalising heat treatment. It is, however, an economical methodofwelding very thick plates and may beused in situations where notch ductility isnotimportant.

11.7 Stud weldingThis is an arc welding process and is extensively used for fixing stud shear coimectors tobeams.

The equipment consists ofagun hand tool, DC power source, auxiliary contactor andcontroller Figure 11.5). The stud is mounted nto the chuck of he hand tool and he

conical tip of he stud isheldin

contact with the work piece by the pressure ofa springon the chuck. The weld is initiated by depressing he trigger on the gun when a solenoidwithin he hand tool comes into operation and causes the stud to lift about 2 mm off hesurface of he work piece; this gap ispreset and can be varied within certain limits. Asmall current pilot arc is hen drawn between he stud tip and the work piece. This isfollowed by the main power arc which melts the end of the stud and he adjacent part of hework piece. Whilst he arc is still burning, he solenoid is de-energised and the springloaded stud plunges nto the molten crater, the duration of he current flow and the timingof the plunge is controlled by a imer in the control unit. High transient weldingcurrents, in the region of2000 amps for a25 milli-second duration for a 19 mm diameter

stud are used and such high currents necessitate the use of an auxiliary contactor whichlimits he current rise at he end of he cycle by switching in a resistance n series withthe power unit.

Fixed clamoing head

Flgur. 11.4 Consumable guide electros!ag welding (ESW)



FIgure 11.5 Schematic ircuit orarc stud welding

The stages of he welding operation are shown in Figure 11.6. A ceramic ferrule placedaround the stud foot is shaped so that an all round fillet is formed. The ferrule alsoprevents ejection ofweld metal and helps to reduce arc glare. To reduce oxidation of theweld metal by the atmosphere, the conical surface at he end of he stud is reated with adeoxidant n the form of aluminium metal spray or a "slug" ofaluminium inserted at thetip; this also improves the mechanical properties of he stud weld.

Composite beam construction in floors of arge buildings often utilises a thin profiledsteel deck spanning the girders; this deck, which is nvariably galvanised, is used as

permanent shuttering and bottom reinforcement o the concrete. To provide forcompositeaction, shear stud connectors are welded o the beams and aproblem can arise when hestuds have to be welded through he galvanised sheet. Zinc will volatilise n the arcdrawn between tud and beam and when he weld ismade it can exhibit gross porosity andfusion defects. One method of educing hese defects and to produce a satisfactory weld isto increase the arcing time of he stud and thus remove he zinc from the arc before theweld is made. Another method, which produces satisfactory welds, is to use actual currentprocess in which a preliminary arc is made first to bum off he zinc on the profiled sheetand then a higher arc current isdeveloped o make he stud-to-beam weld through hesheet.

Liii/ /7ISet-up Pilot arc Main arc

Wcldcd stud

FIgure 11.6 Sequence in welding shear stud connectors

11-6

3-phase transformer and rectifier Auxiiisrycontactor

Controller

SolenoidControl cable

Work piece



11.8 Manual metal arc (MMA)electrodesMMAelectrodes should comply with BS 639(') Specification forcovered carbon andcarbon manganese teel electrodes for manual metal-arc welding.

It s notpossible o grade electrodes on the basis ofmechanical results which relatedirectly o practice because of he very many different ways in which heelectrodes are

used, e.g. welding position, electrode size, nm sequence, welding current and he greatvariety ofparent material upon which he electrodes are deposited. At best therefore anelectrode standard can provide a system by which various ypes ofelectrodes can be gradedin accordance with a specified manner ofweld depositions and esting which is free fromthe effects ofvariations present in practical welding. By this means electrodes ofdifferent ype ormanufacture an be compared. Whilst such grading ofelectrodes can neverindicate the results which will be obtained in any given welding procedure est, inpractice hey form auseful guide to the welding engineer as to what type ofelectrode hewifi need to adopt to achieve satisfactory mechanical test results.

Ordering electrodes complying with this standard gives an assurance of electrode qualityand the classification has significance to the fabricator. The user is advised o carryout welding procedure tests ifnotch oughness criteria have to be satisfied and hesetests should be representative of he appropriate production joints as specified inBS 4870: Part (1)• Furthermore if a fabrication is to be heat treated after welding asimilar post-weld heat treatment should be applied to the welding procedure est piecesbecause heat reatment can affect both the tensile and impact strength.

Different manufacturers may have anumber ofelectrodes with identical or very similar

classifications and the user's choice may depend upon other factors such as ease ofuse,deslagging orwelder appeal (weldability). Electrodes bearing identical codings may beexpected o have generally similar characteristics and properties, even ifmade bydifferent manufacturers, but some differences may exist between such electrodes. Theselection ofelectrodes should be made on the basis of he particular application and heusershould consult the electrode manufacturers or other appropriate authoritative sourcesfor guidance.

If he classifications of he standard are used for purchasing itshould be made clear thatthey represent minimum requirements since electrodes with higher oughness properties thanthe minimum required may also be appropriate foruse on aproduction joint. Furthermorethe manufacturer's brand name or identification number should also be quoted.

For electrodes of agiven type to be classified the manufacturer must est wo sizes -a4 mm and the largest size he wishes to have classified. The results of he two sets oftests are considered.

In accordance with the standard, the classification of an electrode s ndicated asfollows:

(a) Strength, toughness and covering code (STC code)

(1) The letter "E" for amanual electrode.(2) Two digits ndicating the strength tensile, yield and elongation properties of the

weld metal).(3) A digit indicating the temperature for aminimum average impact value of 28 J.(4) A digit indicating the temperature for aminimum average impact value of 47 J.(5) A letter or letters indicating the type of covering.



(b) Additional coding

The following additional coding has to beprovided n manufacturers' literature:

(1) When appropriate, three digits indicating he nominal electrode efficiency.(2) A digit indicating the recommended welding positions for the electrode.

(3) A digit indicating the power supply requirement.(4) When appropriate a letter "if' indicating a Hydrogen controlled electrode.

A guide to the coding system is given in Table 11.1.

The following examples illustrate he way in which he coding isexpressed and the use ofthe complete classification or only the compulsory part.

Example (a)Covered electrodes formanual metal-arc welding having a ruffle covering (R) butnotdesignated as ahigh efficiency electrode.

The electrode may be used for welding n all positions and it welds satisfactorily onalternating current with aminimum open circuit voltage of50 Vand on direct current withpositive polarity. The electrode isnot designed to give hydrogen controlled weld metal.

The electrode deposits weld metal with the properties given in Table 11.2 when ested inaccordance with this standard and when he manufacturer ubmits 8 mm diameter electrodes asthe maximum size to be classified. The table of results shows that the manufacturercarried out sets of impact tests at 00, at -20°C and at -30°C in order to determine theappropriate classification.



T

e11Gd

oco

nsyem

D

G

OFO

T

LEP

E

C

N

Ee

o

d

g

o

dg

T

e

se

h

nmm

yed

Se

Mnmmeo

ow

dgoim

aus

—O

2

345

E

—

E

—

Nm

Nm

%

%

%

4

5

5

6

3

2 1

2 1

2 2

E

CE

B

b

c

B C

b

chgece

cuoc

R

rue

R S

rue(h

c

e

oh

ty

%re

yo

n

e1%

(1%

1

(H Ince

h

o

c

oe

(5m/O

C

SO

SC

A

TO

E

5

4

B

1

3

0

(H

DG

FOM

V

U

J

I

r4

Frs

Dg

Tm

aue°Co

im

uo2

4m

ee

o

oy

EO

E1

E2—

E3

E4

E5—

Ns

e

÷ 0 -2 -3 -4

EE

RC

DGT

W

DN

PO

TO

1

ap

o

2ap

o

e

c-dw

3

aa

o

ewdh

z

a-

v

c

4

a

5

av

c-dwa

o

ewd

h

z

a-v

c

9a

p

oocmnoop

o

ca

ea

S dg

Tm

aue°Co

im

uo4

4ma

lag

eeo

sme

foca

co

E

0

E

1

E—

E—

E

4

E—

E—

E—

E—

Ns

e

+ 0 -2 -3 -4 -5 -6 -7

C

Dre

c

e

Aenn

e

R

m

ee

o

pay

Mnmmo

crc

va

0

Pa

ya

rem

b

m

aue

VN

saeo

u

oAC

1 2 3

+- ÷

5 5 5

4 5 6

÷- ÷

7 7 7

7 8 9

+- +

8 8 8



TabI. 11.2 Test esults or example (a)

Property

Test platesfor4 mmelectrode

Test platesfor8 mmelectrodes

ClassificationE43 —- equivalent Result

Tensilestrength(N/mm2)

475 470 430 to 550 Satisfactory

Yieldstress(N/mm2)

345 340 330 mm. Satisfactory

Impactvalue at-30°C J)

42 20)47 27) average49 31) 36

Notrequired

Temperature forimpact value of28 J average butno one value lessthan 16 J

This result sgreater han both35 J and 28 J andthe results aresatisfactory forclassification offirstdigitat -30°C

Impactvalue at0°C (J)

70)75) average65) 70

60)66) average63) 63

impact value of47 J average butno one value essthan 20J

for classificationofsecond digitat 0°C

Impactvalue at-20°C

60)65) average67) 64

42)38) average31) 37

Temperature forimpactvalue of47 J average butno one value lessthan 20J

The average or the8mm electrode hasfailedas t is essthan 47 J

Elongation % 26 25 24 mm' Satisfactory

'Elongation determined from Table IofBS 631) after establlshment of irst mpact digit.

The classification or the electrode s therefore:

STC code

E43 4 2 RStrength (430 N/mm2 to 550 N/mm2)

Temperature forminimum average impact strength of28 J -30°C)

Temperature forminimum average impact strength of 47 J 0°C)

Covering (Ruffle)

Additional code[i 3]

Welding position

Welding current and voltage conditions

Complete classification

l'he complete classification is herefore E434 2 R [i 3]

11-10



Example (b)An electrode ormanual metal-arc welding having abasic covering, with anominalefficiency of 158% and depositing weld metal containing 8 mL ofdiffusible hydrogen per100 g of deposited weld metal.

The electrode deposits weld metal with the properties given in Table 11.3 when ested in

accordance with his standard and when he manufacturer ubmits 6 mm electrodes as themaximum size to be classified. The table of esults shows that he manufacturer carriedout sets of mpact tests at -30°C and at -40°C.

Table 11.3 Test results for example (b)

Property

Test platesfor 4 mmelectrode

Test platesfor 6 mmelectrodes

ClassificationE51 ---equivalent Result

Tensilestrength

(N/mm2)

565 560 510 to 650 Satisfactory

Yieldstress(N/mm2)

400 395 360 mm. Satisfactory

Impactvalue at-40°C (J)

46 20)40 31) average43 42) 37

Notrequired(see 7.3.1)

Temperature forimpact value of28 J average butno one value essthan 16 J

This result sgreater han both35 J and 28J andthe results aresatisfactory forclassification offirst

digitat -40°C


120)110) average106) 112

60)68) average70) 66

Temperature forimpact value of47 J average butno one value essthan 20J

Satisfactory resultsforclassificationof second digitat-30°C


Results fromprevious testgive average37* (seeabove). No

need o repeattest

4 mmelectrodefailed so noneed o est6 mm

electrode

Temperature forimpact value of47 J average butno one value lessthan 20 J

Failed requirementsof 7.3.2

Elongation % 24 23 20 mm. + Satisfactory

OnIy hree values are n fact equired but whichever three values out of he sixare takenthe average s ess than he required minimum of47 .

÷Elongation determined from Table 1 ofBS 6%(1) after establishment of irst mpact digit.

11—11



The classification for the electrode s herefore:

STC code

E51 5 4 BBStrength 510 N/mm2 to 650 N/mm2)

Temperature for minimum average impact strength of28 J (-40°C)

Temperature for minimum average impact strength of47 J (-30°C)

Covering (basic, high efficiency)

Additional code[160 3 0 H]

Efficiency

Welding positions

Welding current and voltage conditions _________________________________

Hydrogen controlled

Complete classification

The complete classification is therefore E 51 54 BB [160 30 H]

11.9 BS 7084: 1988 Carbon and carbon manganese steel tubularcored welding electrodes

The cored wire welding process uses tubular electrodes which are filled with flux or with amixture of flux andmetal powder. They are either used in the self-shielded mode or withan auxiliary shielding gas, usually carbon dioxide or argon/carbon dioxide.

Althoughhere are

applicationsin all branches of

ndustrythe cored wire

welding processhas found more favour in he heavier branches of ndustry. The self-shieldingcharacteristics of some electrodes have made them deal for use outdoors or he offshoreand shipbuilding industries. Wires which use an additional gas shield have found favour nwork-shop ituations, not only for he welding ofcarbon and carbon-manganese steels, butalso for stainless steels. The development of mall diameter lux cored electrodessuitable for welding in all positions has helped he process gain popularity in generalfabrication.

BS 7084(1) includes requirements for continuous tubular metal-cored or flux-cored

electrodes for arc welding with and without shielding gas, and gives details of he systemby which hey are to be classified.

It may not be possible o select anelectrode which s suitable for aparticular weidmentwithout carrying out an appropriate welding procedure testbut he standard will enable thefabricator to make the first step n consumable selection. These electrode wires can beused in a wide variety of situations, e.g. different steels, welding parameters, types ofpower supply and welding position and width of weld weave. The foreword o the Standardemphasises this problem and advises ests to BS 4870: Part (1)



It isnot possible for suppliers to carry out ests on every coil ofelectrode hey supplyto prove tscompliance and therefore the purchaser is advised o ensure hat the supplieroperates aquality system in compliance with the appropriate part of BS5750(1).

When ordering o the standard the purchaser should specify he standard number, heelectrode classification or rade designation and he test certification documentationrequired. Any particular equirements for emper, cast and helix may also be specified.

The classification system is as follows:

The process dentification letter is "T" for ubular cored electrode and this is followedby adigit indicating strength "4" for a tensile range of430-550 N/mm2 with aminimumyield of 330 N/mm2 and minimum elongation of 20% and "5" for a tensile range of510-650 N/mm2 and minimum yield of360 N/mm2 with minimum elongation of 18%.

This is followed by adigit which relates o the test emperature at which he electrode

deposited weld metal in accordance with he method given and achieved aminimum average

impact value of47 Joules.

Unlike some other consumable standards itwas felt o be more ogical for the digit fortoughness to correlate with the temperature of esting and hence digit 2 relates o -20 Canddigit 3 to -30°C and so on.

The next digit in the classification relates to the recommended welding position and thisis followed by a letter either "G" for agas shielded electrode or "N" for a sell-shielded.

There is hen a further etter which ndicates he application and characteristics of he

electrode in accordance with the detailed table. The final letter "H" of he classificationis only written if he consumable can be classed as hydrogen controlled i.e. the weldmetal has less than 15 ml ofdiffusible hydrogen per 100 g when determined in accordancewith BS 6693: Part 5(1) at welding currents and at arc voltage and electrode extensionas specified in BS 7084(1).

The classification or he electrode s herefore: T551GBHStrength 510 N/mm2) I

Temperature for impact value of 47 J -50°C)

Welding position

Gas shielded

Application and characteristics

Hydrogen controlled _____________________

11-13



11.10 BS 4165: 1984 Electrode wires and fluxes for the submergedarc welding of carbon steel and medium-tensile steel

This British Standard specifies requirements for solid electrode wires and for fluxes ofthe submerged arc welding ofcarbon steel and medium - tensile steel having a ensilestrength ofnotmore than 700N/mm2, and sulphur and phosphorous contents not greater than0.06% each such as those inBS 4360(1) and includes weld impact values appropriate tothese steels. The Standard specifies general equirements for all wires and fluxes.

Charpy V-notch impact tests are affected by many factors such as the composition of hewelding wire and the type of welding flux, the effect ofdiluting rom the parent material,the heat input for the weld which in turn is affected by the welding current, arc voltageand travel speed, and the deposition of he weld runs in amulti-run weld. For this reasonit is usual to carry out ests to assess he mechanical properties on all-weld metal testpieces deposited under defined parameters and thus unaffected by the parent metal used inthe preparation of he tests.

The submerged arc process can be used to make butt welds by a two-nm technique, one runfrom each side of he joint, with either square or partially bevelled edges with agenerous root face. Such are the penetrating properties with this process that sound weldcan be obtained without esort to back gouging. The weld metal deposited in this manner isheavily diluted with parent plate and is likely to provide significantly differentproperties to that deposited by a multi-run technique which results in low dilution andprovides essentially all-weld metal results. To cater for these differences in technique,this standard specifies initial weld tests forboth multi-mn and two-mn deposition.These tests are carried out using specified wire sizes and conditions with an appropriategrade ofBS 4360 plate. Testing of hese welded oints comprises tensile, bend and ChaipyV-notch tests and chemical analysis.

It is important o appreciate that, whilst the tests using he two-mn echnique giveresults which approximate to those obtained in practice when welds are carried Out underthe same conditions with equivalent plate material, the test results obtained from theall-weld metal test pieces with the multi-mn echnique may not relate to aproduction typejoint. Nevertheless, the tests specified are suitable forgrading he results obtainedfrom various wire/flux combinations and enable he fabricator to select acombination whichmay be appropriate to his production requirements. However, one should be aware of hefact that Charpy results from the approval ests may not be representative of hoseobtained from production joints.

Inview of he factors which affect the results obtained from aproduction situation, itwill be advisable for the fabricator o carryout awelding procedure test and referenceshould be made to BS4870: Part (1)•

On completion of esting, he wire/flux combination is assigned the appropriate gradingcode which akes the form ofaprefix number elated to the impact test temperature,followed by the letters "M" and/or "T" to indicate multi-run, two-nm or both and finally athree figure number elated to tensile properties of he weld metal. For example, awire/flux combination giving weld metal in a two-mn test with an average impact valuebetter than 35 J at -40°C, a ensile strength n the range 400 N/mm2 to 600 N/mm2 and yieldstress above 300 N/mm2, would have the grading 4T300.

Manufacturers usually supply a range ofwires and fluxes. This standard ncludes a ableof he commonly used wire analyses and adescriptive table of he various ypes of weldingflux. Fluxes are based on various combinations ofcompounds and the ratio ofbasic toacidic components in a flux is known as the Basicity Index.

11-14



Generally high basicity fluxes end to give the best mpact properties, other factors beingequal. This is a complex subject and inall cases where weld metal toughness s mportant,the user s advised o consult he consumable supplier since the notch oughness of weldmetal isa function not only of he flux chemistry but also of he weld metal chemistry andthe weld micro-structure.

Although combinations of wires and fluxes supplied by individual companies may have thesame grading, he individual wires and fluxes from different companies are not necessarilyinterchangeable.

11.10.1 Testing and gradingThe wires and fluxes are to be capable ofcomplying n all respects with the appropriaterequirements and tests in the standard. In particular wire and flux combinations which aresuitable for multi-run, wo-mn echniques or both shall be tested nitially asappropriate. Wire-flux combinations suitable for use on either a.c or d.c are tested on a.c.In all cases the type ofcurrent used in the tests shall be reported. On satisfactory

completion of hese test the flux and wire combinationsare

graded.The grade number is made up of hree parts: aprefix number elated to impact estingtemperature, the letters "M" or "Ta indicating multi- or wo-run echniques and a hreefigure suffix related to minimum yield stress in N/mm2, e.g..:

Grade 2 M 350

Test temperature Multi-run Minimum yield stress of 350 N/mm2 (tensileof0°C strength 460 N/mm2 to 650 N/mm2)

Where both "M" and "T" gradings are approved for aparticular wire/flux combination, thegrade number shall be given separately, e.g. 3M 450/1T450.

11.11 References1. PRATT, .L.

Introduction to the welding of structural steelwork (3rd revised edition)The Steel Construction Institute, Ascot, 1989


11-15



12. STEEL STAIRWAYS, LADDERS ANDHANDRAILING

12.1 StaIrways and laddersThe design and dimensioning of tairways will generally be determined by their intendedpurpose and anticipated volume and frequency ofusage. Important aspects o be consideredwill be safety inuse, ease ofaccess and adequate clearances.

Figure 12.1 illustrates the terms used in stairway construction.

The available space and slope will be a controffing factor in deciding the type of stairwayto be used. Figure 12.2 is achart giving useful recommendations for stairway typesuitable for a given slope.

Stairways should be designed to withstand a load of5 kN,InZ on the plan area of he stair.Such a load will be sufficient to allow for normal mpact and dynamic load effects. Thedesign oad may be reduced to 3 kN/m2 minimum providing his load isnot ess than the loadon the floor to which he stairway gives access. Further details of loor and stairwayloading are given inBS 6399: Part 1(1).

The design and construction details of stairways must be in accordance with the appropriatepart ofBS 5395(1) which is he code ofpractice for the design of stairways and walkways;BS 4211(1) covers he design of fixed ladders forpermanent access.

12.2 HandrallingHandrails and guardrails are produced o give safety and reassurance for users of tairwaysand walkways. As ageneral rule, any unprotected edge of awalkway, platform and staircasefrom which aperson may fall more than 0.5 m must be protected by aguardrail.

Handrails must be designed to withstand a ateral oad which will depend on the type ofuse. BS 6399: Part J(1) gives the design oad for light access stairs and the loading forhandrails n industrial locations are given in BS 5395: Part 3(1) If here is apossibility

ofvehicular mpact then the recommendations in Appendix C ofBS 6180(1) should be followed.

12.3 Detailed designGuidance and detailed information with regard to the design of stairways, ladders andhandrailing can be obtained from the references at the end of his Section.



FIgure 12.1 Stairway terms

I)a)1.a)E

E

Ca)

cc1I—

250

200

150

FIgure 12.2 Stairway ype recommendations

12-2

Rise ofstair

use

Pitch line,/ç: or rake

Single rung90° ladders Companion,step

5°or ship type ladders

DANGEROUSAccident-prone

rang•

STAIRS

Tread Go in millimetres



12.4 LIst of manufacturersStairs, handrails and ladders

Allan Kennedy & Co LtdRiversideStockton-on-Tees Telephone: 0642 245151

Cleveland TS18 1TQ Fax: 0642 224710

Steelway-Fensecure (GlynwedEngineeiing Ltd)Queensgate WorkBilston Road Telephone: 0902 451733Wolverhampton WV2 2NJ Fax: 0902 452256

Guardrails

Abacus Municipal LtdSutton in Ashtleld Telephone: 0623 511111Nous NG175FT Fax: 0623552133

Orsogiil UK LtdPrudential Buildings95-101 Above Bar Street Telephone: 0703 638055Southampton SO! OFG Fax: 0703 636975

Optimum Safety Fencing LtdThe Coal WharfHighfields Road Telephone: 0902 403197Bilston WV14OSF Fax: 0902402104


(see Section 19)

Further Reading

2. Catalogue and Technical Guide, Steelway and FenscureGlynwed Engineering Ltd, Wolverhampton

3. HAYWARD, A. AND WEARE, F.Steel detailer's manualBSP Professional Books, Oxford 1989

4. Engineering Equipment Users Association E.E.U.A.) Handbook No 7, London(Now E.E.M.U.A. Engineering Equipment and Manufacturers Users AssociationHandbook No 7)



13. CURVED SECTIONS

13.1 GeneralThe development ofpowerful cold-rolling quipment capable of accurately bending he largersizes of tructural sections has greatly ncreased the possible uses of urved members nstructural steelwork. The availability of arge size curved structural sections opens upnew scope for he design ofdomed and vaulted roofs, splayed columns, glazed atria andmalls and for specific features such as, arched intels etc. They are of particular valuefor curved facades since it is usually more economical to fix cladding panels directly ocurved perimeter beams or rails than to use a series of traight members with complexconnectors. Universal beams pm-cambered with great accuracy, can be used in theconstruction ofgraceful ootbridges.

The capacity chart (Figure 13.1) lists hemain

profiles whichcan

be curved by"cold-rolling".

13.2 MinImum bend radiiThe minimum adius o which any section can be curved depends on its metallurgicalproperties, particularly its ductility, cross-sectional geometry and its end use.Table 13.1 gives some typical radii to which a range of ections can be curved. Thisinformation s provided as aguide to scale only, as the bending specialists should alwaysbe consulted when he design of urved members sbeing considered. Them are widevariations n the "bendability" ofdifferent sections. Even within one serial size, theheavier sections can usually be curved to a smaller radii than the lighter sections.Similarly sections can usually be rolled to smaller radii on the y-y axis than on the x-xaxis. Generally, the radii to which hollow sections can be cold-rolled are much largerthan those for I sections ofsimilar size. However, it is possible by the use ofhot orcold bending by mandrels to bend hollow sections o very small radii, e.g. circular ubesup to 139.7 mm. o.d. (outer diameter) can be bent to 3 x o.d., but the process sinevitably more expensive han cold-rolling.

13.3 MaterIal properties ofcurved membersThe cold-rolling process deforms he material hrough heyield point into the plasticrange and the material becomes work hardened. Compared with the original material, thework hardened material of he curved section will have ahigher effective yield andultimate stress but at the expense of ome oss ofductility. The extent ofwork-hardeningdepends mainly on the section geometry and he degree ofbending. For most structuralsteelwork applications, stress relieving will not be required. The non-fatigue "elastic"behaviour of he curved members can be taken as that of he original straight member but itwould be wise to limit the design moment capacity

toM1(i.e. Elastic modulus x Design

strength).

It s important when dealing with cold-worked sections to the normal good steelwork designto detailing practice, avoiding orexample, multiaxial stresses complicated joints, notches etc.



Flgur. 13.1 Bending capacity data

I-Sections, Channels &HollowSections(Other profiles - angles, tees, rails etc. -can also be curved)

Joists and Universal Beams (X-X axis)

Joists &Universal Beams(X-Xaxis)

All sizes up to*914x419x388kg/m

Universal Columns (X-X axis)

Universal Columns(X-Xaxis)

Allsizes up to*356x406x634kg/m

Channels (X-X axis)

Channels(X-Xaxis)

All sizes up to432x102x6.54kg/m

Joists, Beams and Columns (Y-Y axis)

Joists, Beams &Columns

(Y-Yaxis)Allsizes up to'914x419x388kg/m

S.I-LS R.H.S and Solid Bars

Souare Hollow Sections (SHS)Allsizesupto300x300x 16

Rectangular Hollow Sections (RHS)All sizes upto 450x250x 16

Tubes and Solid Bars

Circular Hollow Sections (CHS)

Most sizes up o 406.4 o.d. x 32

Most Euronorm Sizes can also be acxxmmodated.

13-2



Table 13.1 Typicalrecommended end adii

Serial size Typicalpossible bend radii

X-XAxis(metres)

Y-Y Axis(metres)

533 x210 x 122 UB406x 178x 74 UB305x165x 54 UB254x146x 43 UB203x133x 30 UB178x102x 19 UB152x 89x 16 UB127x 76x 13 UB

251875442.52

2.52.2521.751.51.251

1

254x203x81.85RSJ203x152x52.O9RSJ152 x 127 x 7.20 RSJ

42.5

1.5

2.251.75

1.5

305 x 305 x 83 UC254x254x167UC203 x 203 x 86 UC152x152x 37 UC

64.5

32

3.5

32.251.75

250x250x16 SHS200x200x12.5SHS200xlOOxlO RHSl5OxlOOxlO RHS120x 80x10 RHS

10742.52

107

643

219.1 mm x 12.5 mm CHS168.3 mm x 10 mm CHS114.3 mm x 6.3 mm CHS

60.3 mm x 5 mm CHS

31.51.250.75

31.51.250.75

The examples shown are not the minimum radii ossible.

13.4 Bending ofhollow sections for curved structuresThere are all manner of means and equipment available today for he bending ofhollowsections. There is oday very little need for "fire bending" aprocess used until quite

recently for the larger diameter ubes (CHS). By this process the tube is filled withsilver sand, rammed home hard, and the ends plugged with a clay compound o hold the sandfirm and tightly packed. The tube is heated to 950°C by coke-fired or gas-fired ovens nwhatever manageable lengths can be accommodated. The process ishighly skilled and labourintensive, often requiring everal re-heats and water dousing operations to produce abendwith acceptable tolerances. Fabricators using the "fire bending" technique have to bewareofwrinkles on the inside radius, wall hinning and ovality.

13.4.1 induction process for arge radius bending of tubesThese roblems do not occur with the induction process, which isnow used extensively orbending arge diameter ubes.

By this process the tube to be bent ispassed hrough an induction coil where anarrow bandof he tube, approximately 13 mm wide, is raised to a forging temperature while theremainder skept cool by air and water cooling coils.

If required, it is a simple matter to produce a series ofmultiple bends without the needfor ntervening straight sections.

13-3



The narrowness of the heated zone eliminates pipe wrinkling and no formers or supportingmandrels are required, since the cold tube on either side of he heated zone providesadequate support.

Because of he very high speed of induction heating, neither he outside nor inside wall ofthe tube develops scaling during bending.

As the tube is pushed rather han pulled round he bend, tubes of different wallthicknesses present no difficulties butdo need different heating temperatures nd bendingrates.

13.4.2 Cold bending process for arge radius bending of tubesCold bending by section bending olls is another very satisfactory process for ormingbends in tubes orhollow sections. Because here isno cost nvioved to heat the tube itis often amore economical process than alternatives.

Forming bends by this process is achieved by passing the tube to and fro between hreerollers, two ofwhich drive the tube along while the third pinches t to form the bend.The force required o produce the bend is applied in the same manner as apoint load in thecentre of a simply supported beam.

The minimum radius o which any tube or hollow section can be bent depends on the ductilityof he material, cross-section geometry and its end use. The last-named is often thedetermining factor when the appearance of he work has to be ofavery high quality.

Tube becomes oval when bending by this process and, as the radius becomes ighter,wrinkling starts to occur along the inside edge of he radius, and wall hickness thinningoccurs along the outer edge of he radius. The stage at which ovality and wrinkling isunacceptable varies with each application.

Some guidelines or the minimum radius for any particular diameter, that can be achievedare:

O/D Tube Mm. radius

76mm 600mm114mm 800mm127mm 1000mm168mm 1500mm178mm 2000mm219mm 3000mm

In cold rolling process he material is deformed hrough he yield stress into the plasticrange. As a result it becomes "work hardened" which n turn changes the mechanicalproperties. In particular t oses the yield plain characterisitcs and some ductility.However, within he elastic range the stress strain performance isnot alteredsignificantly. The change inproperties can be important however where there is a fatiguestress ora ow temperature condition.

13.4.3 Small radius bending of tubes

Rotary Draw Bending Process saccepted as the most satisfactory process for small radiusbending of ubes andhollow sections.

In this process the tube is ocked to the former die by the clamp die; a mandrel isinserted to aposition where bending akes place. As the former die rotates he pressuredie advances with the tube; this supports the back of the tube as it is being drawn off hemandrel during he bending operation.



Machines are available to bend tubes by this process up to and including 114 mm diameter,the limitation to this process isonly in the range of ormer dies available whichestablishes the centre ine radius hat can be achieved forevery size of ube orhollowsection.

13.5 Accuracy ofbendingItshould be noted that n accordance with Clause 7.2.7 ofBS 5950: Part2(1) thedeviation fmm the specified camber ordinate at the mid-length of he portion to be curvedshould not exceed he greater of 12mm or 1 mm/rn length ofcurved member. Modem bendingmachines usually allow greater accuracy than his.

The above information was supplied by:The Angle Ring Company LimitedBamshaw Section Benders LimitedWestbury Thbular Stnictures Limited

13.6 References1. BRITISH STANDRDS INSTITUTION

(see Section 19)



(a) Atmospheric environments

Stainless steels are not affected by clean, moist air, but some may be attacked by pollutedair with high sulphur or chloride contents, such as will be found in industrial areas or nmarine and coastal environments. The higher alloyed steels offer better resistance ocorrosion, but are also more expensive. For most conditions outdoors n the UnitedKingdom, f surface inish and appearance are important, the 316 type should be used.

Further guidance is given inReference

(1).(b) Swimming pool environments

Special care should be taken in he use of stainless steel in swimming pool or similarenvironments and in particular, with roof and ceiling fixings. Under certain conditions ofstress, elevated temperatures and presence ofchlorides, he protective oxide film isbroken down giving rise to "stress corrosion cracking". See Reference (2).

(c) Chemicals

Stainless steel is resistant o attack from many chemical agents but expert advice shouldalways be sought. Stainless steel producers are often willing to provide such advice.

14.4 StainingStainless steel is compatible with most building materials; it can be used safely incontact with orembedded n concrete or plaster, and will not cause staining ofmarble orother ight-coloured material with which it is in contact. The wash from it will not causestaining of adjacent materials.

14.5 Surface finishDependent on the finishing processes of he sheet, the material can be given adull, mattorbright finish, and it can be polished. Complex shapes can be polished electro-chemically.Textured finishes can be produced by rolling orpressing although care must be excercisedin planning the cutting of heets o use the material economically.

14.6 Fabrication

The high ductility of austenitic steel allows it o be bent to very small radii, but becauseitwork hardens, much greater oads are required for forming and pressing han are requiredfor mild steel, and annealing may be necessary after abrication. Joints can be made bylock-seaming, soldering, brazing, welding and adhesives, but for brazing and fusion weldingthick materials t may be necessary to use either low carbon steel or steels stabilised bythe addition of itaniwn or niobium.

The choice of oining method must be made with regard to service as well as fabricationconditions, and requires expert advice. Note that t is mportant to use separatefabrication areas and tools formild steel and stainless steel to avoid possiblecontamination of he stainless steel.

14.7 ApplicatIons and design considerationsCompared weight forweight with other building materials, stainless steel is expensive, butits properties of strength and corrosion resistance hould be considered in relation o theweight that can be saved. For economy, components should be as thin as possible(Figure 14.1 shows suggested thicknesses or various applications) and the least expensivealloy and form (usually roll-finished) suitable for he application should be selected. Itslow thermal expansion makes itparticularly useful in he design of arge panels or sections,

but very large, flat areas can suffer from optical distortion unless the sheets are supportedby battens. If continuous backing is not feasible, the use ofpatterned rather han polishedsheets should be considered; care should be taken to use apattern hat does not retaindirt.

14-2



Gauge Thickness Application(swg) (mm)

3.50

door bumpers,bent10 framing etc.

3.00

I 12

A 2.50

column covers, interiorsI where bumping byI crates, baggage, etc is

not expected.I 14I 2.00

rollformed, long 16I self-supporting 1.60

roofing, braced panelsmembers but not backed up.B

I cold formed and 18 street furniture, class B.braced for stiff 1.20 bus shelters, lamp posts.-ness, supportedat edges

tOO window sections20 (unsupported)

:backed up by 0.80domestic water tubinguother material 22

24 gutters, exposed0.50 flashing and residential2628 roofing.30

0.25 cladding of windowcore sections.

A. includes treet evel column covers, fascia panels, mullions and transoms, pilasters -stiffened with braces but not completely backed up.

B. includes curtain walls, spandrels, mullions and transoms above street evel.

FIgure 14.1 Suggested hicknesses forvarious applications



The steels are available in he following forms: plate, sheet, strip, bar, sections (hot-rolled,extruded, drawn, and especially cold formed), forgings, tubes (solid drawn and welded),wire and castings.

The durability of tainless steel could be used in the reduction ofmaintenance costs.Little advantage would be gained inapplications of simple and cheap replacement or whereoccasional changes are required for aesthetic or decorative purposes. The advantages liein

applicationsof

permanent strength,function or

appearancesuch as

nails, fixingsand

ties, especially those positioned out of sight, embedded n building materials orunderground.Externally he material is used in roofing generally, and for flashings and weatherings,where failure could lead to troublesome internal damage, particularly with buildings notsubjected to routine inspection. Attention is again drawn to the need for special care inthe use of stainless steel in swimming pools or similar environments.

14.8 Material gradesAs stated above n Section 14.2, the austemtic grades of tainless steel are the most

appropriate for building applications, and types 304 and 316 are the most generallyspecified. In plate, sheet and strip form, these materials are produced o BS 1449:Part 2: 1983(e), the mechanical properties are given in Table 14.1.

Stainless steels with a0.2% proof stress approximately 40% higher are produced toBS 1501: Part 3: 1990(e); the higher level being attained by the inclusion ofnitrogen.The mechanical properties of this plate material are given in Table 14.2.

Table 14.1 Mechanical roperties ofstainless steel o BS 1449: Part 2(e)

Grade0.2% Proof stressN/mm2(min.)

Tensile strengthN/mm2(min.)

Elongation%

Condition

304S11* 180 480 40 Softened

304S15304S16 195 500 40

304S31 195 500 40

316S11*

316S13 190 490 40

316S31316S33 205 510 40

*Denotes stainless steels witha ow carbon content

Table 14.2 Mechanical roperties ofstainless steel to BS 1501: Part (3)

Grade

0.2% ProofstressN/mm2 (mm.)

1% ProofstressN/mm2 (mm)

TensilestrengthN/mm2 (mm.)

Elongation

%

304S61 (270) 305 550 35

316S61 (280) 315 580 35



14.9 References1. NICKEL DEVELOPMENT INSTiTUTE

An architect's guide on corrosion resistanceNickel Development Institute, Toronto, January 1990

2.PAGE, C.L.,

andANCHOR,

R.D.Stiss corrosion cracking of stainless steels in swimming poolsThe Structural Engineer. Volume 66, No. 24., p.416, December 1988, London


AcknowledgmentInfonnation for the above section was obtained from the BRE Digest 121 September 1970"Stainless Steel as a Building Material".



15. FIRE PROTECTION OF STRUCTURALSTEELWORK

Structural sections used in buildings may or may not require fire protection depending uponthe situations in which they are used. If fire protection sneeded, the requirement is hat

the steel iskept below he limiting emperature as defined inBS 5950: Part (1)(2).

Traditionally this has been assumed to be 550°C but in Part 8 the limiting temperature isdefined as a function of the load on the member. Many proprietary materials boards, sprays,intumescents and preformed systems) are available to protect structural steelwork (seeSection 15.3).

Filling hollow steel sections with water orconcrete to provide ire protection can eliminateor reduce he need for additional protection.

Fire protection ofcolumns can also be eliminated or reduced by positioning them outside

the shell of the building.

Designers should refer for fuller details of ire protection requirements, methods of ireprotection, and fire protection materials to the publications listed in Section 15.10.

15.1 SectIon factorsThe performance of a structural steel member n fire depends on the relative proportion ofthe steel surface exposed, i.e. its heated perimeter Hp) and the thickness of teel, whichis related to its cross-sectional area (A). The ratio Hp/A is the section factor.

Hp = Perimeter of the section exposed o fire (m)A = Cross-sectional area of he steel member m2)The lower the Hp/A value, he slower will be the rate ofheating ina fire.

15.2 Forms of protectionThere are three main types of ire protection that should be considered (Figure 15.1) andthey are described below.

Profile protection is where he fire protection follows the surface of he member.Therefore he section factor relates o the proportions of the steel member.

Box protection is where here is an outer casing around he member. The heated perimeterisdefined as the sum of the inside dimensions of he smallest possible rectangle, aroundthe section, neglecting air gaps etc. (refer to Figure 15.1). The cross-sectional area, A,is that of he steel section. The thermal conductivity of he protection material sassumed to be much lower than that of steel and therefore, he temperature conditionswithin the area bounded by the box protection are assumed to be uniform.

Solid protection iswhere he member is encased (typically by concrete). This is a morecomplex case because of he non-uniform thermal profile hrough he concrete. If only partof he member s exposed (for example the lower flange), then the heated perimeter may betaken around he portion that is exposed. This assumes hat the passage ofheat throughthe concrete relative to the steel is small.

15-1



PROFILE PROTECTION BOX PROTECTION

•8 - -:

oj :iijjjj;;::H.2D.3B-2t H.2D+8

3-SIDED PROTECTION

H,.2D.4B-2t

4-SIDED PROTECTION

:H-20.28

SOLID PROTECTION

FIgure 15.1 Different orms of ireprotection o 1 section members

15.3 Performance ofproprietary ire protective materialsAnumber ofdifferent forms ofproprietary fire protective materials are marketed. In

simple erms these are:• cementitious-type sprays, such as perlite-cement, vermiculite, vermiculite-cement.

glass ormineral fibre-cement sprays

• fire boards, such as fibro-silicate, gypsum and vermiculite• mineral ibre and other similar mat materials• intuniescent coatings.

There are anumber ofdifferent manufacturers ofeach of these systems. Sprayed fireprotection appears o be currently popular n commercial steel buildings where the floorsoffit ishidden and where additional cladding is provided around the steel columns. Boxor board systems are more popular where he protection to the beams and columns s eftexposed.

Sprayed systems are usually applied in anumber of ayers. A priming coat applied to thesteel section may be recommended by the manufacturer. The main advantage of sprayedsystems is that they can easily protect complicated beam-column junctions, russes and

l Th i i i th d d d

BOX WITH AIR GAPS



Board systems often use additional noggings and filler pieces between he flanges of hebeam which he boards are aUached. Their method of ointing is mportant in order oprevent gaps opening up. Pm-formed box systems are also used.

Intumescent coatings are those which expand or "intumesce" on heating, thereby offeringprotection o the steelwork. They are generally used for architectural reasons where hesteelwork s eft fully exposed. Thin intuinescent coatings 1 to 2 mm thick) can provideup to 14 hour fire resistance.

15.4 Amount ofprotectionThe amount of ire protection required depends upon the configuration ofprotection, fireresistance period, and the Hp/A value of he section involved. Information in manufacturersliterature is presented n either graphical or abular formats and aknowledge of he Hp/Avalue of he section involved s essential to decide he protection thickness.

The method of determining the thickness of fire protection nBS 5950: Part 8(') isbased on the European approach where temperature dependent properties of he protection are

inserted into adesign formula. Traditionally, the "Yellow Book", Fireprotection orstructural steel in buildings(4) has been used. In this publication, tables are presentedwhich are derived from a semi-empirical approach based on the results of ire tests.Infomiation on the use of traditional material such as concrete, blockwork and brick, maybe obtained from the BRE publication (14)•

15.5 Calculation of Hp/A valuesThe section actor Hp/A isnot aconstant or agiven section but will vaiy according owhether he protection forms abox encasement or follows the profile of he section forboth 3 sided or 4 sided attack from fire.

The value ofHp, the exposed perimeter, depends upon he configuration of he fireprotection. In he case ofbox protection, Hp is measured as the perimeter of shortestlength which will enclose he section, whilst forprofile protection he Hp value is akenas the perimeter of the steel. The equations given in Section 15.5.1 demonstrate how Hp iscalculated for various steel sections in different situations. No account is taken of theradii at the corners of the sections.

In all situations, values ofA, the cross-sectional area of he section, are taken fromtables for the various serial sizes and weights per metre. Hp/A values for universal

beams,universal columns and hollow sections are

givenin the Tables 15.1 to 15.5. It s

normal inpublished tables to quote the section factor to the nearest 5 units.

15.5.1 UnIversal beams, columns and joists

r'Df I

I Lt

Boxprotection B Proffle protection

Boxed (4 sided exposure) Profile (4 sided exposure)

Hp=2B÷2D Hp=2B+2D÷4(Bj.t)

15-3



Boxed (3 sided exposure) Pmffle (3 sided exposure)

Hp=B+2D Hp=B+2D+4t)15.5.2 Hollow sections

Circular hollow section Rectangular hollow section

Hp = tD Hp= 2B + 2D (4 sided)Hp = B + 2D(3 sided) r 2B + D (3 sided)

The shape ofhollow section is such that the perimeter s he same for both profile and boxprotection.

A similar approach hould be used for channels, angles and tees. Detailed advice is givenin the Reference (4).

Specific examples are presented below to show how Hp/A values are estimated for differentsituations o demonstrate the principles.

(i) Solid or hollow box protection

Consider a203 mm x 203 mm x 52 kg/rn universal column, solid or box exposed on four sides,as an example.

_____ID

Hp, (4-sided) 2D + 2B inmA = Cross-sectional area of steel element in m2.

In this case:

B =203.9mmD = 206.2 mmHp = (2 x 206.2) + (2 x 203.9) = 820.2 mm = 0.8202 mA = 66.4 cm2 =0.00664 m2

H 'A—°8202 m —124 -1P'0.00664 m2

m

15-4

D



(ii) Proffle protectionConsider a406 mm x 178 mm x 60 kg/rn universal beam, profile exposed onfour sides, as anexample.

IIn this case:

B = 177.8mmD =406.4mmt =7.8mm

Hp = (2 x 06.4) + (2 177.8) (177.82

7. 8) = 1508.4 mm = 1.5084 mA = 76.0 cm2 = .0076 m2

H IA_l.5084m —198 -1P/ 0.0076m2 m

(iii) Rectangular hollow ections

Consider a300 x 300 x 10 RHS, exposed on four sides, as anexample.

For rectangular hollow sections here is no distinction between box and profileprotection.

B

Hp, (4-sided) = 2B+ 2D + 2(B - t)inmA = Cross-sectional area of steel element in m2.

ProfileProtection

BoxProtection

Hp = 2B +2D (4 sided exposure)A = Cross-sectional area from tables.In this case:D =B=300mmHp =(2x300)+(2x300)= 1200 mm= 1.2mA =116cm2=0.0116m2

Hp/A =0. 16mm2 = 103 rn-1

For oncrete illed RHS, please refer to Design manual or SHS concrete illed columns(11)from British Steel General Steels -Welded Tubes.

15-5



Table 15.1 Hp/Avalues foruniversal eams.

Universal beams D

y

Designation Depth WidthTlckness Area

Serial Mass per section section Web Flange ofsize metre

DB t

Isection

Section factor Hr/AProfile Box

3 sides 4 sides 3 sides 4 sides'///I

I__._J

-

I_....J

mm kg mm mm mm mm cm2 m1 rn' m' m'914x419 388 920.5 420.5 21.5 36.6 494.4 60 70 45 55

343 911.4 418.5 (9.4 32.() 437.4 70 80 50 64)914x 305 289 926.6 307.8 19.6 32.1) 368.8 75 80 64) 65

253 918.5 305.5 17.3 27.9 322.8 95 65 75224 910.3 304.1 15.9 23.9 285.2 105 75 S5201 903 303.4 15.2 20.2 256.4 105 (15 80 95

838x292 226 850.9 293.8 16.1 26.8 288.7 85 95 70 81)194 840.7 292.4 14.7 21.7 247.1 1(X) 115 80 90176 834.9 291.6 14 18.8 224.1 110 (25 90 1(X)

762x267 197 769.6 268 15.6 25.4 250.7 90 100 71) 85173 762 266.7 14.3 21.6 220.4 105 115 80 95147 753.9 265.3 12.9 17.5 188.0 120 135 95 110

686x254 170 692.9 255.8 14.5 23.7 216.5 95 110 75 90

152 687.6 254.5 13.2 21.0 193.8 110 120 85 95140 683.5 253.7 12.4 19.0 178.6 115 130 90 105125 677.9 253 11.7 16.2 159.6 130 145 tOo 115

610x305 238 633 311.5 18.6 31.4 303.7 70 80 50 60179 617.5 307 14.1 23.6 227.9 90 105 70 80149 609.6 304.8 11.9 19.7 190.1 110 125 80 95

610x229 140 617 230.1 13.1 22.1 (78.3 105 120 80 95125 611.9 229 11.9 (9.6 159.5 115 130 90 105113 607.3 228.Z 11.2 17.3 144.4 130 145 100 115101 602.2 227.6 10.6 14.8 129.1 145 160 110 130

533x210 122 544.6 211.9 (2.8 21.3 155.7 110 120 85 95109 539.5 210.7 11.6 18.8 138.5 120 135 95 110101 536.7 210.1 10.9 17.4 (29.7 130 145 tOO 115

92 533.1 209.3 10.2 15.6 117.7 140 160 (10 125

82 528.3 208.7 9.6 (3.2 104.4 155 175 120 14045TX191 98 467.4 (92.8 11.4 19.6 125.2 120 135 90 105

89 463.6 (92 10.6 17.7 113.9 130 145 100 11582 460.2 191.3 9.9 (6.0 104.5 140 160 105 12574 457.2 190.5 9.1 14.5 94.98 155 175 115 13567 453.6 189.9 8.5 12.7 85.44 170 190 (30 (50

457x152 82 465.1 153.5 10.7 18.9 104.4 130 145 lOS 12074 461.3 152.7 9.9 17.0 94.99 140 155 115 (3067 457.2 151.9 9.1 15.0 85.41 155 175 125 14560 454.7 152.9 8.0 (3.3 75.93 (75 195 140 164)52 449.8 152.4 7.6 10.9 66.49 200 220 160 180

406x 178 74 412.8 179.7 9.7 16.0 94.95 140 160 105 12567 409.4 178.8 8.8 14.3 85.49 155 175 115 144)60 406.4 177.8 7.8 (2.8 76.01 175 195 (30 15554 402.6 177.6 7.6 10.9 68.42 (90 215 145 (70

406x140 46 402.3 142.4 6.9 11.2 58.96 205 230 (60 18539 397.3 141.8 6.3 8.6 49.40 241) 270 190 220

356x171 67 364 173.2 9.1 15.7 85.42 140 160 105 (25

57 358.6 172.1 8 13.0 72.18 165 190 125 1455) 355.6 171.5 7.3 11.5 64.58 185 210 135 (6545 352 171 6.9 9.7 56.96 210 241) (55 (85

356x 27 39 352.8 126 6.5 10.7 49.40 215 240 (70 (95

33 248.5 (25.4 5.9 8.5 41.83 250 280 195 225

305x165 54 310.9 166.8 7.7 13.7 68.38 160 185 115 14046 307.1 165.7 6.7 11.8 58.90 185 210 (30 164)40 303.8 165.1 6.1 (0.2 51.50 210 240 150 (80

305x 127 48 310.4 125.2 9.9 14.0 60.83 160 180 (25 14542 306.6 124.3 8 12.1 53.18 180 205 140 164)37 303.8 123.5 7.2 10.7 47.47 200 225 155 180

305x102 33 312.7 102.4 6.6 10.8 41.77 215 240 175 20028 308.9 101.9 6.1 8.9 36.30 245 275 200 22525 304.8 101.6 5.8 6.8 31.39 285 315 225 260

254x146 43 259.6 147.3 7.3 12.7 55.10 (70 195 120 ISO37 256 146.4 6.4 (0.9 47.45 (95 225 140 1703) 251.5 146.1 6.1 8.6 40.00 234) 265 160 200

254x 102 28 260.4 102.) 6.4 (((.1) 36.19 220 254) 170 20025 257 101.9 6.1 8.4 32.17 245 281) 190 22522 254 101.6 5.8 6.8 28.42 275 315 215 250

203x 33 30 206.8 133.8 6.3 9.6 38(X) 210 245 (45 184)

25 203.2 (33.4 5. 7.8 32.3) 240 285 165 210

203x 02 23 203.2 101.6 5.2 9.3 29 235 270 175 210

178x 02 (9 (77.8 101.6 4.7 7.9 24.2 265 305 191) 230

152x89 16 1524 88.9 4.6 7.7 20.5 27(1 3(0 191) 235127x76 13 127 76.2 4.2 7.6 16.8 275 32(1 195 244)



Table 15.2 Hp/Avalues foruniversal olumns' .......! —Universal columns

D IL..r ITT

Section factor He/AProfile Box

3 sides 4 sides 3 sides 4 sides

7///////////i'///r'!

———

rL_

v////////////I

I

L J

r_____I

:

I

L

Designation Depth

ofsectionD

Width

ofsectionB

Thickness

— —Web Flanget T

Areaofsection

Serialsize

Mass permetre

mm kg mm mm mm mm cm2 m m1 nr1 m'356x406

356x 368

305x305

254x254

203x203

152x 152

634551467393340287235202177153129

28324019815813711897

1671321078973

867160

5246373023

474.7455.7436.6419.1406.4393.7381.0

374.7368.3362.0355.6

365.3352.6339.9327.2320.5314.5307.8

289.1276.4266.7260.4254.0

222.3215.9209.6

206.2203.2

161.8157.5152.4

424.1418.5412.4407.0403.0399.0395.0374.4372.1370.2368.3

321.8317.9314.1310.6308.7306.8304.8

264.5261.0258.3255.9254.0

208.8206.2205.2

203.9203.2

154.4152.9152.4

47.642.035.930.626.522.618.5

16.814.512.610.7

26.923.019.215.713.811.99.9

19.215.613.010.58.6

13.010.39.3

8.07.38.16.66.1

77.067.558,049.242.936.530.227.023.820.717.5

44.137.731.425.021.718.715.431.725.320.517.314.220.517.314.212.511.0

11.59.46.8

808.1701.8595.5500.9432.7366.0299.8257.9225.7195.2164.9

360.4305.6252.3201.2174.6149.8123.3

212.4167.7136.6114.092.9

110.191.175.8

66.458.847.438.229.8

25303540455065

708090

105

4550607585

100120

607590

110130

95110130150165

160195245

30354045556575

8595

110130

55607590

105120145

7590

110130160

110135160180200190235300

1520202530304045505565

303540505560754050607080

607080

95105

100120155

20253035354550

60657590

404550657085

100

50657590

110

8095

110

125140

135160205

15-7



Table 15.3 Hp/Avalues forcircularhollowsections

D

Circular hollowsections Section

factor Hr/AProfile or Box

Designation Massper

metre

Areaof

section ''utsidediameter

D

Thickness

t

mm mm kg cm2 rn'21.326.933.7

42.4

48.3

60.3

76.1

88.9

114.3

139.7

168.3

193.7

219.1

3.23.22.63.24.02.63.24.03.24.05.03.24.05.03.24.05.03.24.05.0

3.65.06.35.06.38.0

10.05.06.38.0

10.0

5.06.38.0

10.012.516.0

5.06.38.0

10.012.516.020.0

1431871.992.412.932.553.093.793.564.375.344.51

5.556.825.757.118.776.768.38

10.39.83

13.516.816.620.726.032.020.125.231.639.023.329.136.645.355.970.1

26.433.141.651.663.780.198.2

1.822.382.543.073.733.253.944.834.535.576.805.747.078.697.339.06

11.28.62

10.7013.212.517.221.421.226.433.140.725.7

37.140.349.729.637.146.757.771.289.3

33.642.153.165.781.1102125

3703554153452854103402753352702253302702203252652153252602102852101702051651351102051651301052051651301058570

205165130lOS856555

continuedSection

factor Hr/AProfile or Box

Designation Massper

metre

Areaof

section 'l\. ' L____JOutsidediameter

D

Thickness

t

mm mm kg cm2 m244.5

273.0

323.9

355.6

406.4

457.0

508.0

6.38.0

10.012.516.020.0

6.38.0

10.012.516.020.025.0

6.38.0

10.012.516.020.025.0

8.0

10.012.516.020.025.0

10.012.516.020.025.032.0

10.012.516.020.025.032.040.0

10.012.516.1)

37.046.757.871.590.2111

41.452.364.980.3101125153

49.362.377.496.0121150184

68.6

85.2106134166204

97.8121154191235295

110137174216266335411

123153194

47.159.473.791.1115141

52.866.682.6102129159195

62.979.498.6122155191235

87.4

109135171211260

125155196243300376

140175222275339427524

156195247

165130105

856555

160130105

85655545

160130105

85655545

130

10085655545

1008065554535

105806550403525

1008065

15-8



Table 15.4 Hp/Avalues forsquare hollow sections

I

Rectangularhollow sections [jJsquare)

—Section

factor Ha/A3 sides 4 sides

Designation Massper

metre

Areaof

section tiizeDxD

Thicknesst

mm mm kg cm2 m m1

20x20

25x25

30x30

40x40

50x50

60x60

70x70

80x80

90x90

100x 100

2.02.52.02.53.03.22.53.03.22.53.03.24.05.02.53.03.24.05.06.33.03.24.05.06.38.03.03.65.06.38.03.03.65.06.38.03.65.06.38.04.05.06.38.0

10.0

1.121.351.431.742(142.152.142.512.652.923.453.664.465.403.7!4.394.665.726.978.495.345.676.978.54

10.512.8

6.287.46

10.112.515.3

7.228.59

11.714.417.89.72

13.316.420.412.014.818.422.927.9

1.421.721.822.222.61)2.742.723.203.383.724.404.665.686.884.725.605.947.288.88

10.86.807.228.88

10.913.316.3

8.009.50

12.915.919.59.20

10.914.918.422.712.416.920.925.915.318.923.429.135.5

42535041034(1290275330280265325275260210175

32027025520517014026525020516513511026022016513011026022016013010522016013010519516013010585

565465550450385365440375355430365345280235425355335275225185355330270220180145

350295215175145

350295215175140290215170140260210170135115

continuedSection

factor Hr/A3 sides 4 ides

Designation Massper

metre

Areaof

section j—---— r-][_}-----ize

DxDThickness

tmm mm kg cm2 m m'

120x 120

140x 140

150x 150

180x 180

200x200

250x250

300x300

350x350

400<400

5.1)6.38.0

10.1)12.5

5.06.38.0

tOo12.5

5.06.38.0

10.012.516.0

6.38.0

10.012.516.0

6.38.0

10.012.516.0

6.38.0

10.012.516.0

10.012.5

16.0

10.012.5

16.0

10.012.516.0

18.022.327.934.241.6

21.126.332.9441.449.5

22.728.335.443.653.466.4

34.243.053.065.281.4

38.248.059.373.091.5

48.160.575.092.6117

90.7112142

106132167

122152192

22.928.535.543.553.0

26.933.541.951.563.0

28.936.045.155.568.084.5

43.654.767.583.0104

48.661.175.593.0117

61.277.195.5118149

116143181

136168213

156193245

1551251(X)8571)

I551251(X)8065

155125IOU806555

125100806550

125100806550

12595806550

806550

756550

7561)

50

210171)13511094)

21(1165135110

94)

21016513511094)70

165130105

8570

1651301058570

1651301058565

1058565

1058565

(058565

15.9



Table 5.5 Hp/A values or ectangular ollow

I[ectangular

hollow sections D

Section_factor_Hr/A3 sides 4 sides

//(/////////i(

iL i

iI'I

II

LI

ii iiii IiI'

:1ii Ii

iiIi

ii IiL JDesignation Massper

metre

Areaof

sectionSizeDx B

Thicknesst

mm mm kg cm2 m' m m'50x25 2.5 2.72 3.47 360 290 43))

3.0 3.22 4.10 305 245 3653.2 3.41 4.34 290 23() 345

50x34) 2.5 2.92 3.72 350 295 4303.0 3.45 4.40 295 250 3653.2 3.66 4.66 280 235 3454.0 4.46 5.68 230 195 2805.0 5.40 6.88 190 160 235

60x44) 2.5 3.71 4.72 340 295 4253.0 4.39 5.60 285 251) 3553.2 4.66 5.94 270 235 3354.0 5.72 7.28 220 190 2755.0 6.97 8.88 181) (60 2256.3 8.49 10.8 150 130 185

80*40 3.0 5.34 6.80 295 235 3553.2 5.67 7.22 275 220 3304.0 6.97 8.88 225 180 2705.0 8.54 10.9 185 145 2206.3 10.5 13.3 (50 12t) 1808.0 12.8 (6.3 125 ((Xi (45

90x50 3.0 6.28 8.00 290 240 354)3.6 7.46 9.50 240 2(X) 2955.0 10.1 12.9 180 145 2156.3 12.5 (5.9 (45 (20 1758.0 15.3 19.5 (20 95 (45

100*50 3.0 6.75 8.64) 290 235 3503.2 7.18 9.14 275 220 3304.0 8.86 11.3 220 175 2655.1) (0.9 13.9 180 145 2156.3 13.4 17.1 (45 115 (758.0 (6.6 21.1 (20 95 (40

l00x60 3.0 7.22 9.20 285 240 3503.6 8.59 10.9 240 2(X) 295

5.0 11.7 14.9 (75 154) 2)56.3 14.4 (8.4 (40 (20 (758.0 17.8 22.7 115 95 (40

120x60 3.6 9.72 (2.4 240 195 2905.0 (3.3 16.9 ISO (40 2(56.3 16.4 20.9 145 115 (708.0 20.4 25.9 115 95 (40

120*80 5.0 14.8 18.9 170 150 2(06.3 (8.4 23.4 (35 (20 1708.0 22.9 29.1 110 95 (35

(0.0 27.9 35.5 90 80 115

150x 4)0 5.0 18.7 23.9 165 (45 2(06.3 23.8 29.7 135 120 (70

8.0 29.1 37.1 ItO 95 (35(0.0 35.7 45.5 90 75 10)12.5 43.6 55.5 70 65 90

160x80 5.0 18.0 22.9 175 (40 2(06.3 22.3 28.5 140 110 lit)

8.0 27.9 35.5 115 90 135(0.0 34.2 43.5 90 75 110(2.5 41.6 53.0 75 60 90

21X)x Ot) 5.0 22.7 28.9 (75 14t) 2106.3 28.3 36.0 (40 ItO (658.0 35.4 45.1 110 90 135

(0.0 43.6 55.5 90 70 11(1

(2.5 53.4 68.0 75 60 91)

(6.0 66.4 84.5 64) 45 70250x SO 6.3 38.2 48.6 (35 1)5 165

8.0 48.0 61.1 lOS 90 134)

10.0 59.3 75.5 85 75 HIS12.5 73.0 93.0 70 60 8516.0 915 117 55 45 74)



15.6 Half-hour fire resistant steel structures,free-standing biockwork-flliedcolumns and stanchions

As a result of ests Carried OuttoBS 476: Part 8(') ithas been shown hat arge universalsections with small section actors (H,/A) have inherent half-hour ire resistance and thiscan be used in the fully exposed stat&to satisfy he minimum requirements ofbuilding

regulations. For smaller universal section sizes, half-hour ire resistance can beachieved by fitting ight weight concrete blocks between he section langes as shown nFigure 15.2. This form ofprotection shields he web and inner surfaces of the flangesfrom radiant and convected heat so that the section will heatup much more slowly han theunprotected ection.

The main advantages are reduced costs, avoidance of he need for specialist fire protectioncontractors on site, occupation of ess floor space and good resistance o mechanicalimpact or abrasion.

Blockwork-filled sections can be used for free-standing columns n buildings with half-hourfire ratings. The half-hour ire rating commonly applies in England and Wales for groundand upper storeys inoffice, shop, factory, assembly and storage buildings up to 7.5 m inheight, and to a range ofother multi-storey buildings in residential, assembly, industrialand storage occupancy roups.

Blockwork-filled sections are also suitable for single-storey buildings where he proximityto the site boundary may require he external wall to have half-hour ire resistance.Another deal use is for the supporting columns for mezzanine floors in industrial

buildings.(Acknowledgement. The information in Tables 15.6 and 15.7 was obtained fmm BREDigest 317(12).)

FIgure 15.2 Small size universal olumn with aerated blockpenetration



Table 15.6 Methods ofachieving half-hour ire resistance nwriaflyoadedfree-standing niversal columns provided oad actor yf)does not exceed 1.5 fornormaldesign)

Serial sizemm

Massper metrekg

ExpoHp/Arn-I Recommended protection method

356 x 406 634551467393

No ire protection required.

356 x406 340 23287 26235 30

356x 360 202 33177 37153 42

129 49305x305 283 23

240 26198 30158 36 Blocking n the webs with137 40 autoclaved aerated concrete118 46 blocks gives a minimum of97 54 30 mm fire resistance

fully oaded incompression254 x 54 167 31 (minimum block density

132 37 —475 kglm3).107 4489 5173 61

203x203 86 4571 5360 6252 69

152 x 152 373023

Apply ire protection (boardssprays or intumescents) as permanufacturers' reççmmendations,or blockworkbo' .

(1) See Fire protection orstructural steel n buildings(4)(2)Exposed H (2x lange width)+ (4 x lange thickness)



Table 15.7 Methods ofachieving half-hour ire resistance inuniversal eamsections acting as stanchions provided load actor (if)does notexceed 1.5 fornormaldesign)

Serial sizemm

Massper metrekg

ExpodHp/At')rn-' Recommended protection method

and arger457x191 9889827467

3740434650

457x 152 82746760

37394347

Blocking inthe webs withautoclaved aerated concreteblocks gives a minimum of

406 x 178 746760

454954

30 mm fire resistance(minimum blockdensity— 475 kg/m3).

356x171 6757

4855

350x165 54 57

305x 127 48 50

254x146 43 63

457x152 52

406x 178 54

406x 140 4639 Apply ire protection (boards,

sprays or ntumescents) as per

356 x 171 51 manufacturers' regçmmendations,45 orblockworkbox(').

356x 127 3933

305x 165 4640

305x 127 4237

305x 102 332825

254x 146 3731

(1) See Fire protection for structural teel n buildings(4)(2)Exposed Hp —(2x lange width)+(4+ lange hickness)(3) This table s based on imitingexposed Hp/Avalue to 69 rn-' and lange hickness

to not less han 12.5 mm.



15.7 Fire resistance of composite floors with steei deckingThe fire resistance of composite floor is nherently good and soffit fire protection israrely necessary. Any floor properly designed fornonnal conditions may be assumed to have30 minutes fire resistance without soffit fire protection. For longer periods two designmethods have been developed, viz the fire engineering method and the simplified method.

15.7.1 Fire engineering method

In this method the strength of he section in both hogging and sagging s calculated. Anyarrangement of einforcement may be used. The method is fully described in Reference (10).

15.7.2 Simplified design for he fire resistance of composite floorsTests (see References (8) and (10)), have shown hat he strength ofcomposite loors withsteel deckings in fire is ensured by the inclusion of ufficient mesh reinforcement n heconcrete slab. The reinforcement can be that required for the ambient emperature designand isnot necessarily additional reinforcement included solely for he fire condition. Asimplified design method for fire resistance has been derived from the results of he firetesting and is presented n the fonn ofDesign Tables, viz. Table 15.8(15) and Table 15.9(15).These Tables can be used provided hat:

(i) Loading

The imposed loads or the floor (live oad and finishings, etc) do not exceed6.7 kN/m2.

(ii) Mesh reinforcement

The reinforcement must have a top cover of between 15 mm and 45 mm and beadequately supported over the entire area of he floor.

(iii) Support conditions

The floors and mesh reinforcement must be continuous over at least one support.

15.7.3 Design ablesTable 15.8 gives the simplified design data for composite floors with trapezoidal profileddecking and applies to deck profiles of45 to 60 mm

depth(see

Figure15.3). For deck

proffles ofdepth D less than 55 mm and spans not greater han 3 m, slab depths may bereduced by 55-D up to amaximum reduction of 10 mm. For deck profiles greater han60 mm slab depths should be increased by D-60.

For composite decks with dovetail deck sheeting he design data is given in Table 15.9.The data applies to deck profiles of 38 to 50 mm depth. For deck profiles greater han50 mm the slab depth should be increased by D-50. In the design ables aminimum deckthickness, t, isgiven this thickness ifnot critical as in fire the deck heats up very quicklyand oses much of ts strength. It should notbe considered as mandatory but as apractical

limit. The benefit of using greater slab depths can be taken into account in some circwnstances(see Reference (10)).

15.7.4 Minor variations

Ingiven circumstances minor ncreases in maximum loading and spans may be taken intoaccount (see Reference (10)).

15-14



Table 15.8 Simplified esign orcomposite labs with rapezoidal ecks

Maximumspan(m)

Firerating(hours)

Minimum dimensions

t(mm)

Slab depth(mm)

NW LWMesh size

2.7

3.0

3.6

1

11442

1

144

2

0.8

0.90.90.9

1.0

1.2

1.2

130 120

130 120140 130155 140

130 120140 130155 140

A142

A142A142A193

A193A193A252

NW—Normal weight concrete

LW — Lightweight concretet — Minimum sheet hicknessImposed oad not exceeding 5kN/m2 (+ 1.7 kN/m2 ceilingand services)

Table 15.9 Simplified esign orcomposite labs with dovetail decks

Maximumspan(m)

Firerating(hours)

Minimum dimensions

t(mm)

Slab depth(mm)

NW LWMesh size

2.5

3.0

3.6

1

154

1

144

2

1

144

2

0.8

0.8

0.9

0.9

0.9

1.0

1.2

1.2

100 100110 105

120 110130 120140 130

125 120135 125145 130

A142A142

A142A142A193

A193A193A252

NW—Normal weight concreteLW — Lightweight concretet — Minimum sheet hicknessImposed oad not exceeding 5kN/m2 (÷ 1.7kN/m2 ceilingand services)

TRAPEZOIDAL DECK

_\_7__\_1__DOVETAIL DECK

F

_ __ _— overall slab depthD — deck depth

FIgure 15.3 Overall slab depth and deck depth



15.8 Concrete filled hollow section columnsThe filling of tructural hollow sections manufactured in accordance with BS 4848: Part (1),with concrete will enhance their fire resistance. The hollow sections can be filled withnormal weight concrete with and without reinforcement which may be either conventionalhigh yield bar reinforcement to BS 4449(1) ordrawn steel fibre reinforcement.

Full nformation with regard to design and flit resistance ofconcrete filled columns sgiven in Reference (11).

15.9 Water cooled structuresThe principle ofwater cooling of tructural elements o provide ire resistance,particularly of columns, is now well established and there are many buildings mainly nEurope and the USA, which employ this method of fire protection. Water cooling worksby the water absorbing the heat applied o the structure and carrying t away from the heatsource by convection, either o acooler part of the structure or to be expelled to atmosphere.The heat can be transmitted by the water remaining as a liquid or by changing to steam.Much more heat will be absorbed

by convertinghe water to steam due to the

latent heat ofvapourisation. However, when steam forms, care must be taken to ensure that the steam canbe efficiently emoved rom the structure. Many ests have demonstrated that provided thestructure remains filled with water, the steel emperatures will not rise sufficiently toendanger he stability of he structure.

For further nformation with regard to use ofwater cooled structures, see Reference 5).

15.10 References1. BRITISH STANDARDS

INSTITUTION(see Section 19)

2. LAWSON, R.M. and NEWMAN, G.M.Fire resistant design of steel structures -Ahandbook o BS 5950: Part 8The Steel Construction Institute, Ascot, 1990

3. EUROPEAN CONVENTION FOR STRUCTURAL STEEL WORKEuropean recommendations for he fire safety of teel structuresECCS Technical Committee 3, 1981 (also Design Manual, 1985)

4. Fire protection for structural steel in buildings 2nd Edition)Jointly published by The Association ofStructural Fire Protection Contractors andManufacturers Limited, The Steel Construction nstitute and Fire Test Study Group, 1989

5. BOND, G.V.L.Fire and steel construction: water cooled, hollow columnsConstrado, Croydon, 1974

6. LAW, M. and O'BRIEN, T.Fire and steel construction: Fire safety ofbare external steelThe Steel Construction Institute, Ascot, 1989

7. NEWMAN, G MFire and Steel Construction: The behaviour of steel portal frames in boundary conditions(2nd Edition)The Steel Construction Institute, Ascot, 1990

15-16



8. CONSTRUCTION INDUSTRY RESEARCH AND INFORMATION ASSOCIATIONFire resistance of ibbed concrete loorsCIRIA, Report 107, London, 1985

9. CONSTRUCTION INDUSTRY RESEARCH AND INFORMATION ASSOCIATIONFire resistance ofcomposite labs with steel decking; Data sheetCIRIA, Special Publication 42, London, 1986

10. NEWMAN, G.M.The fire resistance ofcomposite loors with steel deckingThe Steel Construction Institute, Ascot, 1989

11. BRITISH STEELDesign manual for SHS concrete illed columnsBSC Tubes Division, Corby, 1986

12. BUILDING RESEARCH ESTABLISHMENTFire resistant steel structures: Free-standing blockwork-filled columns and stanchionsBRE Digest 317BRE, Watford, 1986

13. LAWSON, R.M.Enhancement of fire resistance ofbeam by beam to column connections -Technical ReportThe Steel Construction Institute, Ascot, 1990

14. MORRIS, W.A., READ, R.E.H. and COOK, G.M.E.Guidelines for he construction of fire resisting structural elementsBuilding Research Establishment, Watford, 1988

15. BRITISH STEEL GENERAL STEELSFire resistant design of tructural steelwork nformation heetsBritish Steel General Steels, Redcar, January 1991

15 17



16. BRITISH STEEL - SPECIALISED PRODUCTS

This Section provides data on special products manufactured by British Steel and covers:

(i) Durbar floor plates(ii) Bridge and crane rails(iii) Bulb flats(vi) Round and square bars

16.1 Durbar floorplatesNon-slip raised pattern steel plates

Durbar steel plates provide ncreased anti-slip properties, the studs being distributed to

give maximum resistance rom any angle. The absence ofenclosed surface areas makesthe plates self-draining and easy to clean thereby minimising orrosion and ensuringlonger life (see Figure 16.1). Standard sizes and mass ofdurbar plate are given inTables 16.1 and 16.2 respectively.

F 6

#6FI9ure 10.1 Duthar loor plate



CORRIGENDUM Table 16.4 Ultimate oad capacity (kN/mm2) forplates simply suppoited on all ouredgeskN/mm2 stressed to 275 N/mm2should read ________________________________________

kN/m2 Thicknesson plain

mm

BreadthBmm

Length (mm)

600 800 1000 1200 1400 1600 1800 2000

4.5

6.0

8.0

10.0

12.5

34.9

62.1

110

172*

269'

25.519.6

45.334.9

80.662.1

126*97.0

197*152

600800

1000

1200140016001800

600800

10001200140016001800

600800

10001200140016001800

600800

10001200

140016001800

600800

10001200140016001800

22.715.112.6

40.426.822.4

71.147.739.7

112*74.562.1

175'116'97.0

21.713.410.0

8.7

38.523.717.815.5

68.442.231.727.6

107'65.949.543.1

167*103'77.467.4

21.212.68.8

7.16.4

37.722.315.812.711.4

67.039.728.122.620.3

105'62.143.935.4

31.7

163'97.0'68.555.349.5

21.012.28.3

6.35.34.9

37.321.714.811.39.58.7

66.238.526.220.117.015.5

103'60.141.031.5

26.624.3

162'94.0'64.149.241.537.9

20.812.07.9

5.94.84.13.8

37.021.314.210.68.57.46.9

65.837.825.218.815.213.312.3

103'59.139.429.3

23.820.719.2

161'92.3'61.645.837.132.429.9

20.811.87.7

5.64.43.73.3

36.921.113.910.17.96.75.9

65.637.424.617.914.111.910.6

103'58.538.528.0

22.118.616.6

160*91.4'60.143.834.529.125.9

Values withoutan asterisk cause deflection greater han B/100 at serviceability, assumingthat he only dead oad present s due toself-weight.Values obtained using Pounder's formula allowing the corners to ift. See note 4.16 nSteelwork design guide to BS5950: Part 1:1985 Volume 1(1).

16-3



16.1.2 Durbar floor plate fixingsThe recommended ize and spacing ofbolts and welds are given inTable 16.6.

Table 16.6 Recommended size and spacing ofbolts and welds

Thickness Boltdiameter Weld Spacingon plain mm mm size mm mm

Upto8 12 3 600

Over 8 16 5 750

Where loorplates have not been designed to resist horizontal oading through diaphragmaction, holes inclips and holes insupport beams see Figure 16.2) should be made 4 mmlarger than boltdiameter. Where a curb is provided on op of loor plates (see Figure16.2), bolt spacing can be ncreased by up o one third.

Where plates willbe manhandled sizes should be kept within he imitsofa twoman ift,about 2.0 m2 for8 mm plate and 1.5 m2 for 10mm plate.

16-4

Table 16.5 Ultimate load capacity (kN/mm2) forplates encastered on all our edgesstressed to275 N/mm2

Thicknesson plain

mm

BreadthBmm

Length (mm)

600 800 1000 1200 1400 1600 1800 2000

CORRIGEND(jkN/mm2

should readkN

4.5

6.0

8.0

10.0

12.5

477* 368' 335'268 215'

172*

848' 654*477*

595'383'305'

151' 116'681*

106'617'543*

236' 182*132'

165'106'848*

368' 284*207'

600800

10001200140016001800

600800

10001200140016001800

600800

10001200140016001800

600800

10001200140016001800

600800

10001200140016001800

31 6*186'12.9'10.1

8.7

562'331'229'180*156'

100 *573*40.7'31.9'27.7'

156 *

91 8'£37'499*433*

244 *144'995*779*67.6'

322*195*14.2'11.9

573*347*253'21 2'

102 *

588'449*377*

159 *964'702'589'

249 *

151110'92.0'

31 4'181'12.2'9.17.56.7

55.7'32.2'21.7'163'13.4'11.9

99 1'564'386'290'239'21 2'

155 *895'603'454*373*331'

242 *

140 *

942'709'583'51.8*

31 2'179'11.8'

8.66.95.85.3

55.5'31.7'21 0'154'12.3'10.49.4

986'559*374*274'21 8*186'169'

154'882'584'429'341'290'262'

241 *138 *91 2'670'533*453*40.9'

311'177'11.6'8.36.55.34.7

553*31 5'206'14.9'11.69.58.3

983'

367'265'206'170'148'

154 *874'573*41 3'322'266'232'

240 *137 *

895'646'503'41 6'36.2'

258'166'132'

Values withoutan asterisk cause deflectiongreater

han B/100at seiviceability, assumingthat he onlydead oad present s due toself-weight.



Bolts Cak n4mmgap

1 -floorplate

8mm. gop forplates up to 8mm.12mm. gap for

plates over 8mm.

çJU.B./R.S.J.

WELDED

100mmto150mm

2 Bolt ixingat base ofhandrail

FIgure 16.2 Duibar loor plate fixings

16.2 BrIdge and crane railsThe principal section dimensions and properties ofBritish Steel Bridge and Crane Rails aregiven inTable 16.7. (The proffles of he available Bridge and Crane Rails ate shown in

Figuit 16.3)

Further details are available from British Steel on request see Section 16.2.3).

Table 16.7 Bridge and crane ails; section roperties

Section Mass/unitlengthkglm

Dimension mmArea V l Z,cm2 mm cm4 cm4 cm3 cm3

Head Basewidth width HeightA B C

13 Bridge 13.31

16 Bridge 15.9720 Bridge 19.8628 Bridge 28.6235 Bridge 35.3850 Bridge 50.1856 Crane 55.9189 Crane 88.93

101 Crane 100.38l64Crane 165.92

36.0 92 47.5445 108 54.050.0 127 55.550.0 152 67.058.0 160 76.058.5 165 76.076.0 171 102.0

102.0 178 114.0100.0 165 155.0140.0 230 150.0

16.95 21.5 39.01 74.38 14.70 16.1720.34 24.3 64.01 116.34 21.55 21.5425.30 25.8 82.10 192.76 27.66 30.3636.46 28.9 167.45 371.37 44.05 48.8645.06 34.4 265.67 505.23 63.79 63.1563.92 29.3 325.83 719.67 69.81 87.2371.22 438 794.38 685.90 141.24 80.67

113.29 53.3 1493.04 1415.91 245.91 159.09127.88 73.9 3410.78 1266.34 420.47 153.50211.37 67.7 4776.95 5121.70 580.59 445.37

ForA,BandCsee Figure 16.4V — height of entroid above base

'xx — moment of nertia about horizontal axis through centroidmoment of nertia about vertical axis through entroidsection modulus about horizontal axis through entroid

Z)— section modulus about vertical axis through centroid

16-5

Fillet welds50mm ong

4mm gap

u11amClip0/0 angle

sectionU.S/fl. SJ.

BOLTED CLIPPED

Curb Det&ili

R.S.C..8./flS. 1.



Figure 16.3 Profilesofbridge and crane rails

16.2.1 RaIl fixingsThere is a wide range ofproprietary fixings available. Manufacturers' iterature shouldbe consulted before finalising design details.

16.2.2 Form of supply(i) Rail ength and olerance

The maximum lengths normally supplied for ndividual bridge and crane rail sections isgiven inTable 16.8

Table 16.8 The maximum lengths orindividualbridge and crane railsections

Section Length (m)

13 Bridge 9.14416 Bridge 9.14420 Bridge 9.14428 Bridge 15.00035 Bridge 15.00050 Bridge 15.00056 Crane 15.00089 Crane 15.000

101 Crane 12.192164 rane 9.144

16-6

16 kg/rnBridge rail

20 kg/rnBridge rail

13 kg/rnBridge rail

56 kg/rnCrane rail

28 kg/rn 35 kg/rn 50 kg/rnBridge rail Bridge rail Bridge rail

89 kg/rn 101 kg/rn 164 kg/rnCrane rail Crane rail Crane rail

FIgure 16.4 Rail imensions



Sections 13, 16, 20 (Bridge) and 164 (Crane) can be supplied with hot sawn ends and to alength tolerance of either ±25 mm or -0, +50 mm, as specified.

Where ength accuracy is mpoitant, e.g. forwelding, ails should be specially ordered ascold sawn to close length olerance, ± 3 mm. All other sections will be supplied cold sawnto a olerance of± 5 mm.

(ii) End straightness

For continuously welded rack applications, bridge and crane rails should be orderedspecially end straightened for welding when all rail ends will be specially end straightenedand checked against a750 mm straight edge to amaximum ordinate deviation of 1 mm inboth planes.

16.2.3 Technical advice

A echnical advisory service is available from British Steel Track Products on section andmaterial selection, metallurgical, welding and design. When utilising he technicaladvisory service, the following infonnation should be provided:

(i) Maximum wheel load(ii) Maximum dynamic loading(iii) Number ofwheels and minimum diameter(iv) Crane suspension and type (if any)(v) Details ofwheel profile(vi) Method of oining and fixing to gantry(vii) Class ofcrane and application

(viii) Anydimensional or

designlimitations

British Steel Track ProductsMoss BayDerwent HoweWorkingtonCumbria CA14 5AF

Telephone: 0900 604321

16.3 Bulb flatsHot rolledbulb lats withbulbon one side are available in sizes ranging rom 120 mm x 6 mmto 430 mm x 20 mm. Table 16.9 shows he preferred widths and thicknesses.

Bulb slope 30

ri

r2

ri = bulb radiusr2 = radius ofcurvature at corners

Figure 10.5 Bulb latdimensions

16-7

x Cenlroid(ex) -

W dth(b)



Table 16.9 Bulb lats

Preferred thicknesses. Properties about xxaxis (see Figure 16.5)

Size Width ThicknessBulbheight

Bulbradius

Area ofsection

Massper unitlength

Surfacearea perunitlength

Positionofcentroid

Momentofinertia

Elasticmodulus

b t c ri A ox lxx Zxx

mm mm mm mm mm cm2 kg/rn m2/rn cm cm4 cm3

120

140

160

180

200

220

240

260

280

300

320

340

370

400

430

120x678

140x6.57810

160x7

8911.5

180x891011.5

200x8.59101112

220x9

101112

240x9.5101112

260x1 01112

280x1 0.51112

13300x111213

320x11.5121314

340x1 2131415

370x1 2.513141516

400x13141516

430x14151720

6786.578

107

8911.589

1011.58.59

1011129

1011129.5

10111210111210.51112

1311121311.51213141213141512.5131415161314151614151720

1717171919191922

22222225252525282828282831

3131313434343437373740404040434343464646464949494953.553.553.553.553.55858585862.562.562.562.5

5555.55.55.55.56

6667777888889

999

10101010111111121212

12131313141414141515151516.516.516.516.516.51818181819.519.519.519.5

9.3110.511.711.712.413.816.614.6

16.217.821.818.920.722.525.222.623.625.627.629.626.8

29.031.233.431.232.434.937.336.138.741.341.242.645.548.446.749.752.852.654.257.460.658.862.265.569.067.869.673.377.080.777.481.485.489.489.794.1

103115

7.318.259.199.219.74

10.8313.0311.4

12.714.017.314.816.217.619.717.818.520.121.723.221.0

22.824.526.224.425.427.429.328.330.332.432.433.535.737.936.739.041.541.242.545.047.546.148.851.554.253.154.657.560.563.560.863.967.070.270.673.980.690.8

0.2760.2780.2800.3190.3200.3220.3260.365

0.3670.3690.3740.4110.4130.4150.4180.4560.4570.4590.4610.4630.501

0.5030.5050.5070.5460.5470.5490.5510.5930.5930.5950.6360.6370.6390.6410.6810.6830.6850.7270.7280.7300.7320.7720.7740.7760.7780.8390.8400.8420.8440.8460.9070.9080.9100.9120.9750.9760.9800.986

7.207.076.968.378.318.187.929.66

9.499.369.11

10.910.710.610.412.212.111.911.811.713.6

13.413.213.014.814.714.614.416.216.015.817.517.417.217.018.918.718.520.220.119.919.721.521.321.120.923.623.523.223.022.825.825.525.225.027.727.426.926.3

133148164228241266316373411448544609663717799902941

10201090116012961400150015901800186020002130247726102770322333303550376041904460472053705530585061706760716075407920921394709980

10490109801228012930135801422016460172601886021180

18.421.023.627.329.032.539.838.6

43.347.959.855.961.867.876.874.077.785.092.399.695.3

10511312212312613714815316217518419120622122239256266274294313313335357379390402428455481476507537568594628700804

16-8



16.3.1 RollIng tolerances forbulb flats(i) Dimensional tolerance

The permitted dimensional tolerances are given in Table 16.10 below.

Table 16.10 Dimensional olerances

Width b (mm) Thickness t mm)

Radius ofcurvature at

corners r2 (mm) orthicknesses (See Figure 16.5)

over up to Permittedtolerance

over up to Permittedtolerance

over up to Maxr2

120 ±1.5120 180 ±2.0180 300 ±3.0300 430 ±4.0

8 + 0.7, -0.36.5 11.5 + 1.0, -0.38.5 13 + 1.0, -0.4

11.5 20 + 1.2, - 0.4

6 1.56 9 2.09 13 3.0

13 20 4.0

(ii) Variation n mass

The masses shown in the Table 16.9 have been calculated from the cross-section with adensity of0.785 kilogram per square centimetre per metre run.

Permitted tolerance n mass:

+6.0%, - 2.0% of he total mass forconsignments of5 tonnes and over+8.0%, - 2.7% of he total mass forconsignments ofunder 5 tonnes.

(iii) Straightness variationPermitted tolerance rom straight when measured over the entire ength of he bar are givenbelow:

For widths b up to 200 mm, permitted tolerance = 0.0030 x lengthFor widths b from 200 mm to 430 mm, permitted tolerance = 0.0025 x length



16.4 Round and square barsSizes andmasses of he full range of available mund and square bars are given in Table 16.11

Table 16.11 Mass per metre length kg/rn)

Diameteror side Round Square

Diameterorside Round Square

Diameteror side Round Square

mm kg/rn kg/rn mm kg/rn kg/rn mm kg/rn kg/rn1011121314

0.620.750.891.041.21

0.790.951.131.331.54

4546474849

12.4813.0513.6214.2114.80

15.9016.6117.3418.0918.85

100105110115120

61.6567.9774.6081.5488.78

78.5086.5594.90

103.82113.04

1516171819

1.391.581.782.002.23

1.772.012.272.542.83

5051525354

15.4116.0416.6717.3217.98

19.6320.4221.2322.0522.89

125130135140145

96.33104.19112.36120.84129.63

122.66132.67143.07153.86165.05

2021222324

2.472.722.983.263.55

3.143.463.804.154.52

5556575859

18.6519.3320.0320.7421.46

23.7524.6225.5026.4127.33

150155160165170

138.72148.12157.83167.85178.18

176.63188.60200.96213.72226.87

252627

2829

3.854.174.49

4.835.19

4.915.315.72

6.156.60

606162

6364

22.2022.9423.70

24.4725.25

28.2629.2130.18

31.1632.15

175180185

190195

188.81199.76211.01

222.57234.44

240.41254.34268.67

283.39298.50

3031323334

5.555.926.316.717.13

7.077.548.048.559.07

6566676869

26.0526.8627.6828.5129.35

33.1734.1935.2436.3037.37

200205210215220

246.62259.10271.89284.99298.40

314.00329.90346.19362.87379.94

3536373839

7.557.998.448.909.38

9.6210.1710.7511.3411.94

7071727374

30.2131.0831.9632.8633.76

38.4739.5740.6941.8342.99

225230235240250

312.12326.15340.48355.13385.34

397.41415.27433.52452.16490.63

4041424344

9.8610.3610.8811.4011.94

12.5613.2013.8514.5115.20

7580859095

34.6839.4644.5449.9455.64

44.1650.2456.7263.5970.85

260270280290300

416.78449.46483.37518.51554.88

530.66572.27615.44660.19706.50

Suppliers should be consulted regarding availability ofsizes.

16.5 References1. THE STEEL CONSTRUCTION INSTITUTE

Steelwork design guide to BS 5950: Part 1:1985, Volume 1 - Section pmperties andmember capacities, 2nd EditionSCI, Ascot, 1987



17. BRITISH STEEL - PLATE PRODUCTS

17.1 Plate products - range of sizesBritish Steel General Steels supplies plate to a wide range of industries worldwide. Theproducts meet the requirements ofBritish, other National and International standards.Tlse specifications cover steels forstructural, hipbuilding, boiler and pressure vesselapplications as well as more specialised specifications including line pipe and proprietarybrands of quenched and tempered plate. The sizes and masses of ull range of availableplate are given inTables 17.1 to 17.8.

Tabi. 17.1 Mass ofplates (kg per m ength)

Thickness Width (mm)

mm 1000 1250 1500 1750 2000 2250 2500 2750 3000 3250 3500 3750 40005 39 49 59 69 79 88 98 108 118 128 137 147 1576 47 59 71 82 94 106 118 130 141 153 165 177 1887 55 69 82 96 110 124 137 151 165 179 192 206 2208 63 79 94 110 126 141 157 173 188 204 220 235 2519 71 88 106 124 141 159 177 194 212 230 247 265 28310 79 98 118 137 157 177 196 216 235 255 275 294 31412.5 98 123 147 172 196 221 24.5 270 294 319 343 368 39315 118 147 177 206 235 265 294 324 353 383 412 442 47120 157 196 235 275 314 353 393 432 471 510 550 589 62825 196 245 294 343 393 442 491 540 589 638 687 736 785

30 235 294 353 412 471 530 589 648 707 765 824 883 94235 275 343 412 481 550 618 687 756 824 893 962 1030 109940 314 393 471 550 628 707 785 863 942 1020 1099 1178 125645 353 442 530 618 707 795 883 971 1060 1148 1236 1325 141350 393 491 589 687 785 883 981 1079 1178 1276 1374 1472 157060 471 589 707 824 942 1060 1178 1295 1413 1531 1648 1766 188465 510 638 765 893 1020 1148 1276 1403 1531 1658 1786 1913 204170 550 687 824 962 1099 1236 1374 1511 1648 1786 1923 2061 219875 589 736 883 1030 1178 1325 1472 1619 1766 1913 2061 2208 235580 628 785 942 1099 1256 1413 1570 1727 1884 2041 2198 2355 251290 707 883 1060 1236 1413 1590 1766 1943 2120 2296 2473 2649 2826100 785 981 1178 1374 1570 1766 1962 2159 2355 2551 2748 2944 3140120 942 1178 1413 1648 1884 2120 2355 2591 2826 3062 3297 3532 3768140 1099 1374 1648 1923 2198 2473 2748 3022 3297 3572 3846 4121 4396160 1256 1570 1884 2198 2512 2826 3140 3454 3768 4082 4396 4710 5024180 1413 1766 2120 2473 2826 3179 3532 2886 4239 4592 4946 5299 5652200 1570 1962 2355 2748 3140 3532 3925 4318 4710 5103 5495 5888 6280250 1962 2453 2944 3434 3925 4416 4906 5397 5888 6378 6869 7359 7850300 2355 2944 3532 4121 4710 5299 5888 6476 7065 7654 8243 8831 9420350 2748 3434 4121 4808 5495 6182 6869 7556 8243 8929 9616 10303 10990

Values in he table are based on the density ofsteel = 7850 g/m3



TabI. 17.2 Typical size iange of arbon steel plates

5 12 12 12 12 12 12 12 12 12 12

6 13.5 13.5 13.5 13.5 13.5 13.5 13.5 13.5 13.5 13.5 12.5 12.5

7 13.5 13.5 13.5 13.5 13.5 13.5 13.5 13.5 13.5 13.5 13.5 13.5 13.5

8 13.5 13.5 13.5 13.5 13.5 13.5 13.5 13.5 13.5 13.5 13.5 13.5 13.5 11

9 18.3 18.3 18.3 18.3 18.3 18.3 18.3 18.3 18.3 18.3 18.3 18.3 18.3 18.3

10 18.3 18.3 18.3 18.3 18.3 18.3 18.3 18.3 18.3 18.3 18.3 18.3 18.3 18.3 10

-ii- -- -ii- -ii-- i— i- -ii-- -ii- i- i— -5 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19

20 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19

25 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19

30 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19

35 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19

40 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19

45 17 17 17 17 17 17 17 17 17 17 17 17 17 17 17 17 17 17

50 17 17 17 17 17 17 17 17 17 17 17 17 17 17 17 17 16.3 15.4

60 15.3 17 17 17 17 17 17 17 17 17 17 16.9 15.6 15.6 14.6 14.6 13.6 12.8

65 13.1 17 17 17 17 17 17 17 17 17 15.9 14.6 13.4 13.4 12.5 12.5 11.6 11

70 13.1 17 17 17 17 17 17 17 17 17 15.9 14.6 13.4 13.4 12.5 12.5 11.6 11

75 8.4 17 17 16.8 16.8 17 17 17 17 15.3 13.9 12.7 11.6 11.6 10.9 10.9 10.2 9.7

80 7.9 17 17 16.8 16.8 17 17 17 17 15.3 13.9 12.7 11.6 11.6 10.9 10.9 10.2 9.7

90

100

120

140

160

180

200

250

300

350

17 17 15 15 17 17 15.1 15.1 13.6 12.4 11.3 10.5 10.5 9.7 9.7 9.1 8.615.7 15.7 13.5 13.5 15.3 15.3 13.6 13.6 12.2 11.1 10.2 9.4 9.4 8.7 8.7 8.2 7.7

13.1 13.1 11.2 11.2 12.7 12.7 11.3 11.3 10.2 9.3 8.5 7.8 7.8 7.3 7.3 6.8 6.4

11.2 11.2 9.6 9.6 10.9 10.9 9.7 9.7 8.7 7.9 7.3 6.7 6.7 6.2 6.2 5.8

9.8 9.8 8.4 8.4 9.6 9.6 8.5 8.5 7.6 6.9 6.4 5.9 5.9 5.5 5.5 5.1

8.7 8.7 7.5 7.5 8.5 8.5 7.5 7.5 6.8 6.2 5.7 5.2 5.2 4.9 4.9 4.5

7.9 7.9 6.7 6.7 7.6 7.6 6.8 6.8 6.1 5.6 5.1 4.7 4.7 4.4 4.4 4.1

4 4 4 4 4 4 4 4 3.9 3.5 3.2

4 4 4 4 4 4 3.6 3.6 3.2

4 4 4 4 3.5 3.5 3.1 3.1

[]Maximum length nmetres

TypicalspecIfIcatIons nclude:Stnictural SteelsBSEN 10025:1990-Fe 60A, Fe 360BBSEN 10025:1990-Fe 30A, Fe 430B

[II]Not available

Note 1 Carbon steel plates orstructural applications and boiler andpressure vessel applications are alsoavailable to he requirements of SO, Euronorm, ASME, ASTM,Canadian, French, German,

Japanese,Swedish and other national tandards.

Note 2 Carbon steel plates forsho construction are also available in accordance with he requirements ofother major Classification Societies such as American Bureau ofShoping, Bureau Ventas and Detnorske Veritas.

.. WIDTHmm

THICKNESS...mm

>1220 >1250 >1300 >1500 >1600 >1750 >1800 >2000 >2100 >2250 >2500 >2750 >3000 >3050 >3250 >3460 >3500 >3750.27503000 3050 3250 3460 (3500 3750(39&

Boiler and Pressure Vessel SteelsBS 1501 - 151/360, 400, 430BS 1501 - 161/360, 400, 430

Ship QualItiesLloyd'sGrade A

17-2



T.bI. 17.3 Typical ize range of ar&rn-manganese stool plates

.5I 13.5 ia3.12.513.5135 13.5 5 l5,

13.5J 13.513.5

13513.513.5 13.5

ti3.513.5 11

18.3 18.3 18.3 18.3 18.3 18.3 18.3 18.3________________ -18.3 18.3 18.3 18.3. 18.3 18.3 18.3 18.3f18.3 . 18.3 18.3 18.3 18.3 18.3 18.3 18.3

18.3 18.3 18.3 18.3 18.3 . 18.3 . 18.3 18.3

18.3 118.3 18.3 18.3 18.3183118.3 18.3

18.3 18.3 18.3 18.3117.6 17 17

18.3 18.3 i 17.9 17 17 17 17

17.3 17 17 17 17 17 17-F -- F

17 17 117 '17 17 17

[j aximum length n metres [] otavailable

Typical specifications Include:Structural SteelsBS4360:1990- OEE, 43EE, OEE

55C, 55EE,WRgrades

BSEN 10025 - Fe 360C, Fe 3600Fe 430C, Fe 4300

Fe5IOA, Fe5108Fe51OC, Fe5100Fe 1000

Boiler and Pressure Vessel SteelsBS 1501 - 164/360, 400BS 501 -223/460, 490BS 1501 -224/400, 430, 460, 490BS 1501 -225/460, 490

Ship QualitiesLloyd's Grades, B, 0, EAH32, DH32, H32,AH34S, DH34S, EH34SAH36, DH36, EH36

WIDTHmm

THICKNES.mm

>1220 >1250 >1300

< 1250(130015005 12 12 12

6 13.5 13.5 13.542 12

13.5 113.5 13.5

7 13.5 13.5 13.5 13.5 13.5

>1500,>1600fl17501)1800)2000 2100 p2250 >25001'2750 >300O'3O50 >325O,3460.'350O >3750< 6001.< 1 750l 1800 000] 2100[ 2250l2500 2750I> 3000 3050l 3250 3460k 3500I 3750 (3960

8

9

13.5

18.3

13.5

18.3

13.5

18.3

13.5

18.3

13.5

13.5

18.3

13.5

18.3

10 18.3 18.3 18.3 18.3J i8.318.3

12.5 18.3 18.3 18.3 18.3 18.3 118.3

15 18.3 18.3 18.3 18.3 18.3 118.3

20 18.3 18.3 18.3 18.3 18.3

25 18.3 18.3 18.3 18.3 18.3

18.3

30 18.3 18.3 18.3 18.3 18.3 18.3

17.5 17 17 17

40

35 18.1 18.1 17 18.1

17

17

177 17 17

17

17 17

117 17 17

17 17 17

17 17

17 17

'17

17

1] 17

17 17

17

17

17

17

- 17 17U17 17

17 17 1i7i7 17

60 10.6 17 17 17 17 17 17 17 iT 7 17 16.9 15.6 15.6 14.6

65 9.7 17 17 17 17 17 17 17 17 17 15.9 14.6 13.4 13.4 12.5

70 9 17 17 17 17 17 17 17 17 j 17 15.9 14.6 13.4 13.4 12.5

75 84 16 16 16

80 79 15 16 16 16 16 1153 9 12311.6 11.6

90—

16 16 15 15 16 16

13 12A 11.3 10.5 105 97

-i 11.1 .2I

9.4 87i131L2 8.5 7.8 7.8- - - —. 5.8 531 53 4160 10.1 10.1 8.6 8.6 7.6 7.6 6.7 63 6.1 5.5 5.0k

4.7 4.7 4.3

160 9 9 7.7 77 67 63 50 0 54 4.5_4.11 4.1 3200 8.1 8.1 6.9 6.9 6.1 6.1 5.4 5.4 4.8 4.4 4.0 3.5

250 4 4 4 4 4 4 4 4 3.9 3.5 3.233414 -- - —____

350 ' 4 3.5j

3.5 3.1 3.1

17 17

17 163 154

14.6 13.6 112.8I

12.5 11.6 ii12.5 '11.6111

10.9 10.2 9.7

10.9 10.2 9.7

9.7 9.1 8.6

83 8.2 7.7

7373 6.8 6.4

4 4.6

4.3

3.8

4.0

3.6

3.5 3.2

CORTENA, BIHyplus 29Note I Carbon-manganese plates forstructural applications and boiler and pressure vessel applications are

also available to he requirements of SO, Euronorm, ASME, ASTM, Canadian, French, German, Japanese,Swedish and other national standanis.

Note 2 C-Mnplates forship construction are also available inaocordance with he requirements ofothermajor Classification Societies such as American Bureau ofShipping, Bureau Veritas and Dot norskeVeritas.

17-3



TabI. 17.4 TypcaJ size range of owalloy steel plates

118 Maximum ength n metres

Typical pecifications hiclud:

Notavailable

Boilerand Pressure Vessel SteeleBS 1501:Part 2 - allgrades, except hose whichare supplied n the quenched and tempered ondition. (See

appropriate table).

ASTM ASME) - selected grades ormA203, A204, A353and A387.

Lowalloyboiler and pressure vessel steel plates are also available o meet the requirements of SO,Euronorm, Canadian, French, German, Swedish and other national standards.

17-4

WIDTHmm

THICKNmm

<1250 1500'1750 2000 <2250 2500 2750<3000l< 3250k<3500l3750(39605 13.5 13.5 13.5 13.5 12.5 12.5

6 13.5 13.5 13.5 13.5 12.5 12.5

7 13.5 13.5 13.5 13.5 12.5 12.5

8 13.5 13.5 13.5 13.5 12.5 12.5

9 18 18 18 18 18 18 18 18 18

10 18 18 18 18 18 18 18 18 18

12.5 17 17 17 17 17 17 17 17 17 17 17

15 17 17 17 17 17 17 17 17 17 17 17

20 17 17 17 17 17 17 17 17 17 17 17 17

25 17 17 17 17 17 17 17 17 17 17 17 17

30 17 17 17 17 17 17 17 17 17 17 17 17

35 17 17 17 17 17 17 17 17 17 17 17 17

40 17 17 17 17 17 17 17 17 17 17 17 17

45 17 17 17 17 17 17 17 17 17 17 16.6 15.7

50 17 17 17 17 17 17 17 17 17 16.0 14.9 14.2

60

70

80

90

100

120

140

160

180

200

17 17 17 17 17 17 15.6 14.4 13.3 12.5 11.8

17 17 17 17 17 14.6 13.3 12.3 11.4 10.7 10.1

16.0 15.5 16.0 15.6 14.0 12.7 11.6 10.8 10.0 9.3 8.8

16.0 13.7 15.6 13.8 12.5 11.3 10.4 9.6 8.9 8.3 7.9

14.4 12.4 14.0 12.5 11.2 10.2 9.3 8.6 8.0 7.5 7.1

12.0 10.3 11.7 10.4 9.3 8.5 7.8 7.2 6.7 6.2 5.9

11.5 9.9 8.6 7.7 8.1 6.3 5.8 5.3 4.9 4.6

10.1 8.6 7.6 6.7 6.1 5.5 5.0 4.7 4.3 4.0

9.0 7.7 6.7 6.0 5.4 4.9 4.5 4.1 3.8 3.6

8.1 6.9 6.1 5.4 4.8 4.4 4.0 3.7 3.5 3.2



T.bI. 17.5 Typical ize range ofquenched and tempered teel plates

5 15 15 15 15 15 15 15 15 15 15

6 15 15 15 15 15 15 15 15 15 15

7 15 15 15 15 15 15 15 15 15 15

8 15 15 15 15 15 15 15 15 15 159 15 15 15 15 15 15 15 15 15 15 15 15 15

10 15 15 15 15 15 15 15 15 15 15 15 15 15

12.5 15 15 15 15 15 15 15 15 15 15 15 15 15

15 15 15 15 15 15 15 15 15 15 15 15 15 15

20 15 15 15 15 15 15 15 15 15 15 15 15 15

25 15 15 15 15 15 15 15 15 15 15 15 15 15

30 12 12 12 12 12 12 12 12 12 12 12 12 12

35 12 12 12 12 12 12 12 12 12 12 12 12 12

40 12 12 12 12 12 12 12 12 12 12 12 11 11

45 12 12 12 12 12 12 12 12 12 11.9 10.9 9.7 9.7

50 12 12 12 12 12 12 12 11.9 11.9 10.7 9.7 8.8 8.8

55 12 12 12 12 12 12 12 11.5 10.8 9.7 8.8 8.0 8.0

60 12 12 12 12 12 12 11.1 10.6 9.9 8.9 8.1 7.3 7.3

:::.::: Maybe available for15 Maximum length inmetres Notavailable some qualities with

dimensions and propertiesbyarrangement

Note: Quenched and Tempered plates are available withspecif edproperties n hicknesses up to and ncluding40 mm with he exception of:

-QT445 Grade Awhich is only available to 32 mm maximum-RQT5O1, BS 1501:510, ASTMA553 Type 1 which are available up to 50mm maximum

-QT445 Grade Bwhich is available from32 to 63 mm

17-5

WIDTHmm

TMICKNESS'-..mm

<1250 130O \<1 500 <1600 175O <1800 <2000 <2100 2250 <2500 (2750<3000<3050

65 12 12

70

80

90

100

12 12 11.8 11.4 10.3 9.8 9.1 8.2 7.5 6.7 6.7

Typical pecifications Include:Structural Steel high strength toilerquenched and empered)BS4360:1990- Grades 50F and 55F0T445 -Grades AandBRQT5OI, RQT6OI, RQT7O1

ASTMA514SS 142624Wear Resistant Steeis Boilerand Pressure Vessel SteelsA-R-COL BS 1501:510(9% nickel)ARQ280, 300, 320, 340, 360 ASTM A553 Type 1 (9% nickel)

ASTMA517



Table 17.0 Typical ize range ofcarbon and carbon-manganese wide flats

TH CKNESSmr

WIDTH _____________mm

[J Maximum length n metres

Development range-L1 Please consult

Notnormally vailable except byspecial arrangement onstraightnessand latness tolerances

Typical specifications Include:

Structural Steels

BS 4360:1990- allgrades including weatherresistant teels) except grades50F, 55EE and 55FF.

Equivalent structural teel n accordance withforeign national standards are available onapplication.

Not available

F:!:1Maybe available withdimensionsand material propernes byarrangement

17-6

Ship Qualities

Wide Flats n normal and high strengthstructural grades are available inaccordance with he

requirementsof

the major Classification Societiessuch as Lloyds,American Bureau ofShipping, Bureau Veritas and Detnorske Veritas.

10 12 15 20 25 30 35

1280

200

220

250

40 45 50 55 60

13 13 15 15 15

4

150 13 13 13 15 15 15 15 15 15

15 15 15 15 16

12 13 14 15 15 15 15 15 16 16 16 16 16 16

65 70 75 80 90 1O0

16

12 13 14 15 15.5 16.5 17 17 17.5 18 18 18 18 18

16 16

12 13.5 14 15 15.5 16 16.5 17.5 17.5 17.5 18 18 18 18

300 12 14 15 16 18 18 18 18 18 19 19 19 19 19

325

350

375

400

425450

475

500

550

575

600

625

650

12 12 15 16 18 18 18 18 18 19 19 19 19 19

12 15 16 18 18 18 18 20 20 20 20 20 20

12 16 16.5 20 20 20 20 20 20 21 21 21 21

12 16 17 21 21 22 22 22.5 22.5 23 23 23 23

12 16 18 21 23 23 23 23 23 23 23 23 2316 18 21 23 23 23 23 23 23 23 23 23

15 18 21 23 23 23 23 23 23 23 23 23

15 18 21 23 23 23 23 23 23 23 23 23- -- -- -- -- - --- --18 21 23 23 23 23 23 23 23 22 20

18 21 23 23 23 23 23 23 23 21 19

18 21 23 23 23 23 23 23 22 21 19

18 21 23 23 23 23 23 23 21 20 19

18 21 23 23 23 23 23 22 21 19 18



TubI. 17.7 Typical size range ofpmfihing slabs

WIDTH

THICKNE?000 1100 1200 1300 1400 1500 1600 1700 1830

80 11.5to14.0100

120140

160

180200220240 3.5to 14.0

260

280300320340

360

380400425450

Maybe available with14 Maximum length inmetres Notavailable dimensions by

arrangement

Typical specifications kiclude:

BS EN 10025:1990- Fe 430,4, Fe 510A

EN8(88 970 080 A40)

ASTMA36,A572 -50

DIN17100 RSt 37-2, St 44-2, St42-3

Profilingslab tç to 16.0 m may be available depending upon widtMhickness ombination



18. TRANSPORTATION, FABRICATION ANDERECTION OF STEELWORK

This Section provides guidance to designers, abricators and erectors on transportation ofsteel to site and allowable tolerances in fabrication and erection.

18.1 TransportatIon of steelworkThe size of structural units that can be transported will form the upper boundary of sizefor aparticular tructural member. This limitation will therefore form one of theparameters ofdesign. Where the distance o be transported is particularly long orexpensive, care should be taken in designing members so that they can be stacked in theminimum space and where possible nested ogether.

18.1.1 Road transport

The UK Road Traffic Regulations permit a gross weight for rigidvehicles of30 tons and 32

tons forarticulated vehicles. The maximum permitted axle oad is 10 ons. There are alsoregulations concerning the length, width, marking, lighting and police notification forlarge oads. These requirements have been published by Motor Transport Journal andreproduced in Figure 18.1. This chart shows the requirements of he law concerning policenotice and mates, when ong, wide and projecting loads are carried. This chart waspublished in Motor transport ournal June 1988. For fuller details, eference shouldbe made to this issue of the Journal. The requirements are contained in the followinglegislation to which reference may be made for classification:

(1) Motor vehicles (construction & use) regulations 1986(2) Motor vehicles (authorization of special types) general order 1979(3) Road traffic act 1972

The official clearance height fornew bridges over roads in he UK is 5.0 m. Minimumclearance for service roads is4.5 m. However, foragiven project it would be wise tocheck existing bridge clearances, as not all of he older bridges meet these requirements.

Also mportant is he limiting width which should be checked at the same ime.

18.1.2 RaIl transportThe normal imitations of ize that can be transported by British Rail are 21 m longx 2.4 m wide x 2.75 m high. For this ype of freight, weight is not normally aproblem,but all aspects of he journey should be cleared n advance with the appropriate railauthority.

18.1.3 AIrtransportDelivery ofprefabricated steelwork by air ismore complicated due to different types ofaircraft n use. For the normal side loading type ofcargo aircraft, oads have to bepalletised n crates approximately 3.0 m x 21 m x 1.4 m with serious imitations onweight

There are however arger front oading aircraft available. It s recommended that one ofthe cargo charter companies be contacted for up-to-date limitations of size and weight

18-1



FIgure 18.1 Law requirements at a glance

Over 18.3m (6010

18-2

er05mm (12m)

orover2.9m (9ft 61i)

PoliceNotice

required

VehicleMate

required

/I V

IOver 25.9m C85ft)

/ / _/1/V

V

OverI7/IV/v

2.9m (9ft 6)OvAr 35m

Construction & UseCC. and U.)

Special types

Both (C. & U. andSpecial types)

Indivisible loadon C. and U.vehicleAbnormalindivisible oad

Form V.R.I.

Form V.R.I.

(lift 5 314in)

Over4.3m (l4tt)

Over Sm(l6ft 4 3/4in)



18.1.4 Transport by shipThis presents no problem. Any structural member which can be transported to the docksidecan be accommodated aboard ship.

18.2 FabricatIon tolerancesBS 5950:Part 2(1),

specifieshe dimensional tolerances to which steelwork members and

components are to be fabricated and the steelwork structure s to be erected. Thesetolerances have been taken nto account n the provisions ofBS5950:Partl(1) and it isessential that these olerances are achieved so that subsequent difficulties in he locationand/or use of he steelwork components do not arise.

Additional and/or different olerances may be specified to cater for special equirementsofaparticular uilding orproblem but such tolerances should be compatible with thedesign recommendations and product standards.

Thepermitted

maximum deviation fromdesign

dimensions after fabrication of steelworkmembers and the erection of he steelwork structure are set out in unambiguous illustratedformat in he National structural steelwork specylcation or building construction(2).

The above specification covers permitted deviations after fabrication in respect of:

(i) Rolled components (including Structural Hollow Sections)(ii) Elements of fabricated members(iii) Plate girder sections(iv) Box sections

The permitted deviations refer to cross-section squareness, length, camber etc. afterfabrication.

18.3 Accuracy oferected steelworkDesigns are carried outon the basis of mplicit assumptions on the level of workmanshipachievable. Any deviation rom permitted workmanship tolerences could influence heperformance of the building.

Permitted deviations n foundations, walls, foundation bolts and erectedcomponents

arecontained in the National structural steelwork specifications for building construction(2).


(see Section 19)

2. BRITISH CONSTRUCTIONAL STEEL WORK ASSOCIATIONNational structural steelwork specifications forbuilding constructionBCSA Publication No 1/89BCSA, London, 1989

18-3



19. BRITISH STANDARDS

Abasic list ofBritish Standards covering he Design and Construction ofSteelwork(correct as at 31 December 1990)

BoltsBS 3692 1967 Specification for ISO metric precision hexagon bolts, screws and nuts. Metric

units

1967 Specification for ISO metric black hexagon bolts, screws and nuf.s

1968 Specification formetal washers for general engineering purposes. Metricseries

BS 4395 Specification forhigh strength friction gripbolts and associated nuts and washersfor structural engineering. Metric seriesPart 1:1969 General gradePart 2: 1969 Higher grade bolts and nuts and general grade washers

BS 4604 Specification for he use ofhigh strength riction grip bolts in structuralsteelwork. Metric seriesPart 1: 1970 General gradePart 2:1970 Higher grade (j)arallel shank)Part 3: 1973 Higher grade (waisted shank)

BS 4933 1973 Specification for ISO metric black cup and countersunk head bolts and screwswith hexagon nuts

Corrosion

BS 729 1986 Specification for hot dip galvanised coatings on iron and steel articles

BS 1501 Steels for pressure purposes: plates, sheet and stripPart 3: 1990 Specification for corrosion and heat-resisting steels

BS 1706 1990 Method for specifying electroplated coatings ofzinc and cadmium on iron andsteel.

1967 Specification forsurface finish ofblast cleaned steel for painting

1977 Code ofpractice for the protective coating of ron and steel structuresagainst corrosion

Design

BS 466 1984 Specification for power driven overhead travelling cranes, semi-goliath andgoliath cranes for general use

BS 449 Specification for the use of tructural steel in buildingPart 2: 1969 Metric unitsAddendum No. 1 (1975) to BS 449: Part 2 1969The use ofcold formed steel sectionsin building (withdrawn, replaced by BS 5950: Part 5)

BS4190

BS4320

BS4232

BS5493

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BS 2573 Rules for he design of ranesPart 1:1983 Specification for classification, stress calculations and designcriteria for structures

BS 2853 1957 Specifications for the design and esting of steel overhead unway beams

BS 4211 1987 Specification for adders forpemianent access to chimneys, other highstructures, silos and bins

BS 5395 Stairs, adders and walkwaysPart 1:1977 (1984) Code ofpractice for the design of straight stairsPart2: 1984 Code ofpractice for he design ofhelical and spiral stairsPart 3: 1985 Code ofpractice for he design of ndustrial type stairs, permanentladders and walkways

BS 5400 Steel, concrete andcomposite bridgesPart 3: 1982 Code of practice fordesign of teel bridgesPart5: 1979 Code of practice fordesign of composite bridgesPart 6: 1980 Specification formaterials and workmanship: steelPart 10: 1980 Code ofpractice for fatigue

BS 5502 Code ofpractice for he design ofbuildings and structures for agriculturePart 1 Section 1.1: 1986 MaterialsPart22: 1987 Code ofpractice fordesign, construction and loading

BS 5628 Code ofpractice foruse of masonryPart 3: 1985 Material and components, design and workmanship

BS 5950 Structural use of teelwoik n building

Part 1: 1990 Code of practice fordesign in simple and continuous construction:hot rolled sectionsPart2: 1985 Specification for materials fabrication and erection: hot rolledsectionsPart 3: Section 3.1: 1990 Codes ofpractice for design of imple and continuouscomposite beamsPart 4:1982 Code of practice fordesign of floors with profiled steel sheetingPart 5: 1987 Code of practice fordesign of cold formed sectionsPart 6: Code ofpractice for design of ight gauge sheeting, decking and cladding(in preparaton)Part 7: Specification for materials and workmanship: cold formed section (inpreparation)Part 8: 1990 Code ofpractice for ire resistance design

BS 6180 1982 Code ofpractice for protective barners in and about buildings

BS 8110 StructuraluseofconcretePart 1: 1985 Code ofpractice fordesign and constructionPart 2: 1985 Code ofpractice for special circumstances

Erection

BS 5531 1988 Code ofpractice for safety in erecting structural frames

Fire

BS 476 Part 8: 1972 Test methods criteria or the fire resistance of elements ofbuildingconstruction

BS 5950 Part 8: 1990 Code ofpractice for fire resistance design

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Loading

BS 648 1964: Schedule ofweights ofbuilding materials

BS 5400 Steel, concrete and composite bridgesPart 2:1978 Specification for loads

BS 6399 Loading forbuildingsPart 1: 1984 Code ofpractice for dead and imposed oadsPart 2: Code ofpractice for wind oading (to be published and will replace CP3

Chapter V Part 2)Part 3: 1988 Code ofpractice for imposed roof oads

CP3 Code ofbasic data for the design ofbuildingsChapter V Part 2: 1972 Wind oad

Quality Assurance

BS 5750 1989: Quality systems (various parts)

Steel

BS 4 Structural steel sectionsPart 1:1980 Specification for hot rolled sections

BS 970 Specification for wrought steels formechanical and allied engineering purposesPart 1: 1983 General inspection and testing procedures and specific requirements

of carbon, carbon manganese, alloy and stainless steels

BS 1449 Steel plate, sheet and stripPart 1: 1983 Specification for carbon and carbon-manganese plate, sheet and stripPart 2: 1983 Specification for stainless and heat-resisting steel plate, sheet andstrip

BS 1501 Steel for pressure purposes: plates, sheet and stripPart 1: 1980 Specification for carbon and carbon manganese teelsPart 2:1988 Specification for alloy steels

Part 3: 1990 Specification for corrosion and heat-resisting steelsBS 2989 1982 Specification forcontinuously hot-dip zinc coated and iron-zinc alloy coated

steel: wide strip, sheet/plate and slit wide strip

BS 4360 1990 Specification for weldable structural steels

BS 4461 1978 Specification for cold worked steel bars for reinforcement ofconcrete(withdrawn, replaced by BS 4449: 1988)

BS 4449 1988Specification

forcarbon steel bars for the reinforcementof

concrete

BS 4482 1985 Specification for cold reduced steel wire for the reinforcement ofconcrete

BS 4483 1985 Specification for steel fabric for he reinforcement ofconcrete

BS 4848 Specification for hot-rolled tructural steel sectionsPart2: 1975 Hollow sectionsPart4:1972 (1986) Equal and unequal anglesPart5: 1980 Bulb flats

19-3



BS EN 10 002-1 Tensile esting ofmetallic materialsPart 1: 1990 Method of est at ambient temperature

BS EN 10 025 1990 Specification forhot rolled products of non-alloy structural steels andtheir technical delivery conditions

Vibration

BS 6472 1984 Guide to evaluation ofhuman exposure to vibration in buildings (1Hz o80 Hz)

Welding

BS 639 1986 Specification for covered carbon and carbon manganese teel electrodes formanual metal-arc welding

BS 4165 1984 Specification for electrode wires and fluxes for he submerged arc welding ofcarbon steel and medium tensile steel

BS 4870 Specification for approval testing ofwelding proceduresPart 1: 1981 Fusion welding of teel

BS 4871 Specification for approval testing ofwelders working o approved weldingproceduresPart 1: 1982 Fusion welding of teel

BS 4872 Specification for approval testing of welders when welding procedure approval is

not requiredPart 1: 1982 Fusion welding of teel

BS 5135 1984 Specification forprocess ofarc welding ofcarbon and carbon manganesesteels

BS 6693 Diffusible hydrogenPart 5: 1988 Primary method for the determination of diffusible hydrogen in MIG,MAG, TIG or cored electrode ferritic steel weld metal

BS 7084 1989 Specification forcarbon and carbon manganese steel ubular cored weldingelectrodes

Weld Testing

BS 2600 Radiographic examination of usion welded butt joints in steelPart 1: 1983 Methods or steel 2 mm up to and including 50 mm thickPart 2: 1973 Methods or steel over 50mm thick up to and including 200 mm thick

BS 2910 1986 Methods for radiographic examination of fusion welded circumferential buttjoints in steel pipes

BS 3923 Methods orultrasonic examination of weldsPart 1: 1986 Methods ormanual examination of usion welds in ferritic steels

BS 5289 1976 Code ofpractice for visual inspection of fusion welded oints

BS 6072 1981 Method for magnetic particle flaw detection



20. ADVISORY BODIES

The reader may wish to contact one of he Advisory Bodies isted below for additionaland/or current nfonnation and advice on most of he topics covered by this publication.However, please note that most of hese Advisory Bodies give free advice only to theirmembers; membership details can be obtained on request.

1. The British Constructional Steelwork Association (BCSA)The Bntish Constructional Steelwork Association Ltd (BCSA) is the national representativeorganisation for the constructional steelwoik ndustry; its Member companies undertake hedesign, fabrication and erection ofsteelwork or all forms ofconstruction in building andcivil engineering. Associate Members are those principal companies involved in thepurchase, design or supply ofcomponents, materials, ervices, etc. related to theindustry. The principal objectives of he Association are to promote he use of structuralsteelwork; to assist specifiers and clients; to ensure hat the capabilities and activities

ofthe industry are widely understood and to provide members with professional ervices intechnical, commercial, contractual and quality assurance matters.

The British Constructional Steelwork Association Ltd4 Whitehall CourtWestminsterLondon SW1A 2ESTelephone: 071 839 8566 Fax: 071 976 1634

2. The Building Research Establishment (BRE)The Building Research Establishment s he principal organisation in the United Kingdomcarrying out research nto building and construction and the prevention and control offire. BRE ispart of he Department of he Environment. Its main role is to advise DOEand other Government Departments on echnical aspects ofbuildings and fire andon relatedsubject, such as some aspects ofenvironmental protection.

The Establishment's unique range of specialist skills and echnical facilities is madeavailable to the construction industry and its suppliers and clients through BRE TechnicalConsultancy, launched in October 1988.

BRE operates rom foursites: its main site at Garston, near Watford; the Fire ResearchStation at Borehamwood and Cardington; and the BRE Scottish Laboratory at East Kilbride,Glasgow.

Building Research EstablishmentGaistonWatford WD2 7JRTelephone: 0923 894040 Fax: 0923 664010

3. British Steei picBritish Steel operates various centres ofprofessional and technical advice for heconstruction industry. They are listed below by product.

(a) Sections

The Structural Advisory Service comprises a eam of egionally-based engineers specialisingin all aspects of tructural steelwork.

20-1



The service offers confidential advice free ofcharge to designers and specifiers eitherin-house orover the telephone. It also offers a computer-based feasibility study facilityto produce scheme designs ofstructures for comparison purposes with other framingmaterials.

Bntish Steel General SteelsCommercial Division - SectionsP0 Box 24, Steel House

RedcarCleveland TS1O 5QLTelephone: 0642 474111 Fax: 0642 489466

(b) Plates

For nformation and advice on ll aspects of election and se ofcarbon, carbon manganeseand low alloy steel plates, including structural and pressure vessel steels. The serviceis he focal point for all the expertise and research effort required o answer any queryrelating o the use of teel plates.

British Steel General SteelsCommercial Division - PlatesP0 Box 30MotherwellLanarkshire ML1 1AATelephone: 0698 66233 Fax: 0698 66233 Ext 214

(c) Tubes

For information and advice on all aspects ofStructural Hollow Sections SHS) bothRectangular (RHS) and Circular (CHS) - including design, abrication and welding, budgetpricing, fire protection, corrosion prevention and metallurgical aspects.

Regionally based Structural Engineers are available to call at customers' offices to adviseon design and usage.

British Steel General Steels - Welded TubesP0 Box 101CorbyNorthamptonshire NN17 1UATelephone: 0536402121 Fax: 0536 04111

(d) Strip productsThe Technical Advisory Service gives information and advice on the products of BS StripMill Products. This includes dimensional anges, steel qualities, suitability ofproductsforparticular applications, conformity to British and International Standards, andinterpretation of specifications.

British Steel Strip Products

CommercialP0 Box 10NewportGwent NP9 OXNTelephone: 0633 290022 Fax: 0633 272933

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(e) Stainless steel

The Stainless Steel Advisory Centre offers advice on he selection of stainless steels,properties and performance, fabrication, manipulation, surface inishing etc.

The Centre has a comprehensive index of abricators, finished components, mill quantities,and stockholders, which will help with any source of upply queries.

It s he focal point for all the expertise and research effort required o answer anyquestion elating o the use of stainless steel.

Stainless Steel Advisory CentreP0 Box 161

Shepcote LaneSheffield S9 1TRTelephone: 0742 440060 Fax: 0742 448280

4. Constructionndustry

Research and nformationAssociation (CIRIA)The Construction Industry Research and Information Association is an independent

non-profit-distributing body which initiates andmanages research and information projectson behalf of ts members. CIRIA projects relate to all aspects of design, construction,management and performance ofbuildings and civil engineering works. Details ofotherCIRIA publications, and membership subscription ates, are available from CIRIA at theaddress below.

CIRIA6 Storey's GateLondon SW1P 3AUTelephone: 071 222 8891 Fax: 071 222 1708

5. The Steel Construction nstitute (SCI)

The teel Construction Institute aims to promote he proper and effective use of teel inconstruction.

SCI's work is initiated and guided through he involvement of its members on advisorygroups and technical committees. A comprehensive advisory and consultancy service isavailable to members on the use of teel in construction.

SCl's research and development ctivities cover many aspects of teel constructionincluding multi-storey construction, industrial buildings, use of steel inhousing,development ofdesign guidance on the use of stainless steel, behaviour ofsteel infire,fire engineering, use of teel in barrage schemes, bridge engineering, offshoreengineering, development of structural analysis systems and the use of CAD/CAE.

The Steel Construction nstituteSilwood ParkAscotBerkshire SL57QNTelephone: 0344 23345 Fax: 0344 22944

SC! offices also at:

Unit 820 B-3040 HuldenbergBirchwood Boulevard 52 De Limburg StinimlaanWarrington Belgium

Cheshire WA3 7RZ

Telepone: 0925 838655 Telephone: International + 322 687 8532Fax: 0925 838676



6. The Fire Test Study Group (UK) (FTSG)FFSG s a fonim for echnical discussions and iaisons between consulting fire testlaboratories nvolved n producing information for the puiposes ofbuilding control.

Members of he FTSG participate on all relevant BSI committees, the equivalent ISOtechnical committees and are involved n the EEC Commission technical discussions onharmonisation.

The Fire Test Study Group (UK) (FTSG)First Floor72 High StreetPortishead,BristolAvon BS2O 9EHTelephone: 0272 846262

20 4



APPENDIX: Metric conversion tables

Equivalents of SI units are given in Imperial and, where applicable, metric echnicalunits.

MEASUREMENTS

Imperial Imperial

= 0.03937 in=3.281ft= 1.094yd= 0.6214 mile= 0.00155 in2= 10.76 ft2= 1.196yd2= 2.471

acres= 0.00006102 j3=35.3lft= 1.308yd3

unlft1 yd1 mileun21 ft21 yd21

acre1 in31 ft1 yd3

=25.4 mm= 0.3048 m= 0.9144m= 1.609km=645.2mm2= 0.0929 m2= 0.836 1 m2=

0.4047 hectares= 16390mm3= 0.02832 m3=0.7646 m3

N/mm2 tonf/in2 kgf/cm2 N/mm2 tonf/ft2 kgf/cm2

Metricetric

1mmim

1km1 mm21m21m21

hectait1 mm31m3

(Moment of Inertia)1 mm4

FORCE

Ibf

=0.000002403 in4(Moment of nertia)un4 =416200mm4

1.04.4489.807

=0.2248= 1.0= 2.205

kgf= 0.1020= 0.4536= 1.0

FORCE PER UNIT LENGTHN/rn

1.014.599.807

Ibf/ft

= 0.06852= 1.0= 0.672

kN

1.09.9649.807

kN/m

1.032.699.807

N/m2

1.047.889.807

tonf

=0.1004= 1.0= 0.9842

tonf/ft

= 0.0306= 1.0= 0.3000

Jbf//ft2

=0.02089= 1.0= 0.2048

FORCE PER UNIT AREAN/rnmz Ibf/in2

kgf/m

= 0.1020= 1.488= 1.0

kgf/cm2

= 10.20

= 0.0703= 1.0

tonne f= 0.1020= 1.016= 1.0

tonne f/rn

= 0.1020= 3.333= 1.0

kgf/m2

=0.102= 4.882= 1.0

1.00.0068950.09807

= 145.0

= 1.0= 14.22

1.0 =0.06475 = 10.20 1.0 =9.324 = 10.2015.44 = 1.0 = 157.5 0.1073 = 1.0 = 1.0940.09807 =0.006350 = 1.0 0.09807 =0.9144 = 1.0

A-i

Continued



continued

UNITWEIGHTN1m3 lbfIft3 kgf/m3 kN/m3 tonf/f13 tonne /m3

1.0 = 0.006366 = 0.102 1.0 = 0.002842 = 0.1020157.1 = 1.0 = 16.02 351.9 = 1.0 = 35.889.807 = 0.0624 = 1.0 9.807 =

0.02787=

1.0

kN/rn3 Ibf/in3 tonne /m3

1.0 =0.003684 = 0.1020271.4 =1.0 =27.689.807 =0.03613 =1.0

MOMENT

N-rn Ibf-in lbf-ft kgf-m1.0 = 8.85 1 = 0.7376 = 0.10200.1130 =1.0 =0.08333 =0.011521.356 = 12.0 = 1.0 = 0.13839.807 = 86.80 = 7.233 = 1.0

FLUID CAPACITYlitres Imp. gallons USA gallons

1.0 =0.22 = 0.26424.546 = 1.0 = 1.2013.785 =0.8327 = 1.0

A-2

50723682 steel design to bs5950 essential data

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