BS 5950 Design Guide

Steelwork Design Guide to BS 5950-1: 2000 Volume 1 Section Properties Member Capacities 6th Edition (Incorporating Amendment 1 of June 2002)

The Steel Construction Institute and

The British Constructional Steelwork Association Limited

The Steel Construction Institute

Publication P202

Steelwork Design Guide to BS 5950-1: 2000 Volume 1 Section Properties Member Capacities 6th Edition Reprinted, October 2002 (incorporating Amendment 1 of June 2002)

Jointly published by:

The Steel Construction Institute Silwood Park, Ascot, Berkshire, SL5 7QN Telephone: 01344 623345 Fax: 01344 622944

The British Constructional Steelwork Association Limited 4 Whitehall Court, London, SW1A 2ES Telephone: 020 7839 8566 Fax: 020 7976 1634

© The Steel Construction Institute and The British Constructional Steelwork Association Ltd., 2001 © The Steel Construction Institute, 1985, 1987, 1992, 1996, 1997 Apart from any fair dealing for the purposes of research or private study or criticism or review, as permitted under the Copyright Designs and Patents Act, 1988, this publication may not be reproduced, stored, or transmitted, in any form or by any means, without the prior permission in writing of the publishers, or in the case of reprographic reproduction only in accordance with the terms of the licences issued by the UK Copyright Licensing Agency, or in accordance with the terms of licences issued by the appropriate Reproduction Rights Organisation outside the UK. Enquiries concerning reproduction outside the terms stated here should be sent to the publishers, at the addresses given on the title page. Although care has been taken to ensure, to the best of our knowledge, contained herein are accurate to the extent that they relate to either matters matters of opinion at the time of publication, The Steel Construction Institute Steelwork Association Limited assume no responsibility for any errors in or and/or information or any loss or damage arising from or related to their use.

that all data and information of fact or accepted practice or and The British Constructional misinterpretations of such data

Publications supplied to the Members of SCI and BCSA at a discount are not for resale by them. Publication Number:

SCI P202

ISBN 1 85942 124 5

(ISBN 1 85942 124 5, Sixth Edition, reprinted 2002 incorporating AMD 1 of June 2002) (ISBN 1 85942 124 5, Sixth Edition, 2001) (ISBN 1 85942 075 3, Fifth Edition, 1997) (ISBN 1 85942 033 8, Fourth Edition, 1996) (ISBN 1 870004 72 8, Third Edition, 1992, reprinted 1993, 1994) (ISBN 1 870004 26 4, Second Edition, 1987) (ISBN 1 870004 01 9, First Edition, 1985) British Library Cataloguing-in-Publication Data. A catalogue record for this book is available from the British Library.

ii

FOREWORD Sixth Edition, reprinted Oct 2002 (incorporating AMD 1, June 2002) The following pages have amended values for: 1. Surface area per tonne for hot-finished and cold-formed circular hollow sections Pages affected: Yellow B-19, B-20, B-25, B-26, B-27. 2. Compression resistance for cold-formed SHS and RHS in S355 Pages affected: Green D-23, D-26, D-27, D-28, D-29. 3. Compression resistance of back-to-back angles in S275 and S355 Pages affected: Pink C-40, C-41, C-42, C-43; Green D-40, D-41, D-42, D-43. 4. Preloaded higher grade HSFG bolts Pages affected: Pink C-237, C-238, C-239, C-240; Green D-237, D-238, D-239, D-240.

Sixth Edition (First impression, June, 2001) The first edition of this Design Guide was published in 1985; it was revised in 1987 (2nd Edition), in 1992 (3rd Edition), in 1996 (4th Edition) and in 1997 (5th edition). It is a basic working tool for users of BS 5950-1 Structural use of steelwork in building - Code of practice for design Rolled and welded sections, which was first published in 1985, revised in 1990 and in 2000. The 6th edition is a complete revision, updating the information in line with the recently amended Standard, BS 5950-1: 2000. The formats of the capacity tables have been changed where necessary to suit the amendments to BS 5950-1. As a result of the changes in the recent amendments to BS 5950-1, many of the tabulated member capacities and resistances have changed. Whilst some values have increased, in the following areas some values have reduced: •

Buckling resistance moment for Class 3 sections

•

Tension capacities

•

Resistances to combined axial load and bending

•

Resistances to web bearing and buckling

The following structural sections are covered in the 6th Edition: •

Universal beams, Universal columns, joists, bearing piles, parallel flange channels, and structural tees cut from Universal beams and Universal columns to BS 4-1

•

Castellated Universal beams and columns

•

ASB (asymmetric beams) Slimdek® beam produced by Corus (see Corus brochure, Structural sections 3/2001)

•

Equal and Unequal angles to BS EN 10056-1

•

Hot-finished structural hollow sections to BS EN 10210-2

•

Cold-formed structural hollow sections to BS EN 10219-2

Section ranges listed are intended to be in line with sections that are readily available at the time of printing. Some sections, which are readily available but not listed in the above standards, are also included; these sections are highlighted in the tables. The preparation and editorial work for the 6th Edition was carried out by Mr A G J Way and Mr A S Malik, with technical assistance from Mr C M King and Mr J C Taylor, all of the SCI. The project was coordinated by Mr D G Brown, of the SCI, and Mr P J Williams, of the BCSA. This publication has been jointly funded by SCI and BCSA. Acknowledgement is also given to Corus for its support for the work leading to the preparation of the initial formulae on which the capacity tables are based. iii

The major differences between the 6th Edition (2001) and the 5th Edition (1997) are: •

This edition is in accordance with BS 5950-1: 2000.

•

Cold-formed circular, square and rectangular hollow sections are now included.

•

Parallel flange channels are included.

•

Tapered flange channels have been omitted but are still included BS 4-1.

•

All the section property pages and member capacity tables have the design standard and the product standard quoted in the top left hand corner. e.g.

•

Design Standard

BS 5950-1: 2000

Product Standard

BS4-1: 1993

Tables giving effective section properties for compression, bending and combined axial and bending have been added. In BS 5950-1: 2000 effective section properties are now required for class 3 semi-compact sections and class 4 slender sections.

Previous Editions 1st Edition, 1985 Based on the following codes: BS 5950: Part 1: 1985, BS 4360: 1979 including Amd 1 and Amd 2. UB, UC, joists, bearing piles and channels to BS4: Part 1: 1980 including Amd 1 and 2. Structural hollow sections to BS 4848: Part 2: 1975. Angles to BS 4848: Part 4: 1972 including Amd 1 and Amd 2. Section properties calculated from imperial dimensions and then converted to metric. 2nd Edition, 1987 An update of 1st Edition including changes due to: BS 4360: 1986. UB, joists to BS4: Part 1: 1980 Amd 3. Angles to BS 4848: Part 4: 1972 Amd 3. Addendum No.l to 2nd Edition, 1990. Section properties and member capacities for a new range of additional hollow sections. 3rd Edition, 1992 Combination of 2nd Edition and Addendum No.l. plus changes due to: BS 5950: Part 1: 1990 Including Amd 1. BS 4360: 1990 and BS EN 10025: 1990. UB, UC, joists, bearing piles and channels to BS4: Part 1: 1980 including Amd 1 to 5. Structural hollow sections to BS 4848: Part 2: 1991. Angles to BS 4848: Part 4 including Amd 1 to 3. In addition to minor corrections, the major alterations in the 3rd Edition were as follows: Section properties based on true metric dimensions instead of metric equivalent of inch dimensions. Member capacity tables for struts made of angles and channels revised due to code changes. Combined axial load and bending tables presented in a more user-friendly format with separate checks for local capacity and overall buckling.

IV

3rd Edition, (Reprinted) 1993 (Reprinted with minor corrections) Supplement A to 3rd Edition, 1994 Section properties and member capacities for UB, UC, bearing piles, joists and associated tees and castellated sections using the dimensions from BS 4: Part 1: 1993. Additional information such as formulae for reduced plastic modulus, warping constant (H) and torsion constant (J). 3rd Edition (Reprinted) 1994 Reprinted with reference to Supplement A. 4th Edition, 1996 Combination of 3rd edition (reprint) 1994 and Supplement A, 1994. Minor changes in Explanatory notes and Table headings for clarity and consistency. Summary of sections covered: UB's, UC's, joist and bearing piles to BS 4: Part 1: 1993 (as per Supplement A). Channels to BS 4: Part 1: 1993 (as per 3rd Edition). Structural hollow sections to BS 4848: Part 2: 1991 (as per 3rd Edition). Angles to BS 4848: Part 4 1972 (as per 3rd Edition). 5th Edition, 1997 Combination of 4th edition, 1996 (except for structural hollow sections to BS 4848: Part 2) and new tables for structural hollow sections to EN 10210-2 Minor changes for clarity and consistency in Explanatory Notes and under the tables for structural hollow sections. Summary of sections covered: UB's, UC's, joist and bearing piles to BS 4: Part 1: 1993 (as per 4th Edition) Channels to BS 4: Part 1: 1993 (as per 4th Edition). Angles to BS 4848: Part 4: 1972 (as per 4th Edition). Structural hollow sections to EN 10210: Part 2: 1997.

CONTENTS Page No (White pages) A

EXPLANATORY NOTES

A-1

1

GENERAL 1.1 Material, section dimensions and tolerances 1.2 Dimensional units 1.3 Property units 1.4 Mass and force units

A-1 A-1 A-2 A-2 A-2

2

DIMENSIONS OF SECTIONS 2.1 Masses 2.2 Ratios for local buckling 2.3 Dimensions for detailing

A-2 A-2 A-2 A-2

3

2.3.1

Universal beams, universal columns and bearing piles

A-2

2.3.2

Joists

A-3

2.3.3

Parallel flange channels

A-3

2.3.4

Castellated sections

A-3

SECTION PROPERTIES 3.1 General 3.2 Sections other than hollow sections

A-3 A-3 A-3

3.2.1

Second moment of area (/)

A-3

3.2.2

Radius of gyration (r)

A-3

3.2.3

Elastic modulus (Z)

A-4

3.2.4

Buckling parameter (u) and torsional index (x)

A-4

3.2.5

Warping constant (H) and torsion constant (J)

A-5

3.2.6

Plastic modulus (S)

A-6

3.2.7

Equivalent slenderness coefficient (

a

)

and monosymmetry index ( 3.3

4

a)

A-9

Hollow sections

A-10

3.3.1

Common properties

A-10

3.3.2

Torsion constant (J)

A-10

3.3.3

Torsion modulus constant (C)

A-10

3.3.4

Plastic modulus of hollow sections (S)

A-11

EFFECTIVE SECTION PROPERTIES 4.1 General 4.2 Effective section properties of (except angles) 4.3 Effective section properties of (angles) 4.4 Effective section properties of 4.5 Effective section properties of and bending

A-12 A-12 members subject to compression A-12 members subject to compression members subject to pure bending members subject to axial compression

vi

A-13 A-1 3 A-14

5

6

CAPACITY AND RESISTANCE TABLES

A-15

5.1 5.2

A-15 A-15

General Design strength

COMPRESSION TABLES 6.1 Compression members: UB sections, UC sections, joists, and hollow sections 6.2 Compression members: Single parallel flange channels 6.3 Compound compression members: two parallel flange channels 6.3.1 T w o parallel flange channels laced 6.3.2 T w o parallel flange channels back to back 6.4 Compression members: single angles 6.5 Compound compression members: two angles

A-15 A-18 A-19 A-19 A-19 A-20 A-21

7

TENSION TABLES 7.1 Tension members: Single angles 7.2 Compound tension members: Two angles

A-23 A-23 A-24

8

BENDING TABLES 8.1 Bending: UB sections, UC sections, joists and parallel flange channels 8.2 Bending: Hollow sections

A-24

9

A-15

A-24 A-25

8.2.1

Circular and square hollow section

A-25

8.2.2

Rectangular hollow sections

A-26

WEB BEARING AND BUCKLING TABLES 9.1 UB sections, UC sections and joists: bearing, buckling and shear capacities for unstiffened webs 9.2 Parallel flange channels: bearing, buckling and shear capacities for unstiffened webs 9.3 Square and rectangular hollow sections: bearing, buckling and shear capacities for unstiffened webs

A-26 A-26 A-28 A-29

10 AXIAL & BENDING TABLES 10.1 Axial load and bending: UB sections, UC sections, joists, and parallel flange channels 10.2 Axial load and bending: hollow sections

A-32

11 BOLTS, WELDS AND FLOOR PLATES 11.1 Bolt capacities 11.2 Welds 11.3 Floor plates

A-36 A-36 A-39 A-39

12 REFERENCES

A-42

VII

A-32 A-34

B.1 TABLES OF DIMENSIONS AND GROSS SECTION PROPERTIES (Yellow pages) Universal beams

B-2

Universal columns

B-8

Joists

B-12

Universal bearing piles

B-16

Hot-finished circular hollow sections

B-19

Hot-finished square hollow sections

B-21

Hot-finished rectangular hollow sections

B-23

Cold-formed circular hollow sections

B-25

Cold-formed square hollow sections

B-28

Cold-formed rectangular hollow sections

B-30

ASB (Asymmetric beams)

B-34

Parallel flange channels

B-36

Two parallel flange channels laced

B-40

Two parallel flange channels back to back

B-41

Equal angles

B-43

Unequal angles

B-44

Equal angles back to back

B-46

Unequal angles long leg back to back

B-47

Castellated universal beams

B-48

Castellated universal columns

B-52

Structural tees cut from universal beams

B-54

Structural tees cut from universal columns

B-58

VIII

B.2 TABLES OF EFFECTIVE SECTION PROPERTIES (Blue pages)

Universal beams subject to compression

B-62

Hot-finished circular hollow sections subject to compression

B-64

Cold-formed circular hollow sections subject to compression

B-64

Hot-finished square hollow sections subject to compression

B-65

Cold-formed square hollow sections subject to compression

B-65

Hot-finished rectangular hollow sections subject to compression

B-66

Cold-formed rectangular hollow sections subject to compression

B-67

Equal angles subject to compression (Reduced design strength)

B-68

Unequal angles subject to compression (Reduced design strength)

B-69

Universal beams subject to pure bending

B-70

Universal columns subject to pure bending

B-71

Hot-finished circular hollow sections subject to pure bending

B-72

Hot-finished square hollow sections subject to pure bending

B-73

Hot-finished rectangular hollow sections subject to pure bending

B-74

Cold-formed circular hollow sections subject to pure bending

B-76

Cold-formed square hollow sections subject to pure bending

B-77

Cold-formed rectangular hollow sections subject to pure bending

B-78

Universal beams subject to compression and bending

B-82

Universal columns subject to compression and bending

B-86

Hot-finished square hollow sections subject to compression and bending

B-88

Hot-finished rectangular hollow sections subject to compression and bending

B-90

Cold-formed square hollow sections subject to compression and bending

B-94

Cold-formed rectangular hollow sections subject to compression and bending

B-96

IX

Steel Grade S355 S275

CD MEMBER CAPACITY TABLES

(Pink pages)

(Green pages)

C-2

D-2

C-6

D-6

C-8

D-8

C-9

D-9

C-11 C-13 C-18* C-18* C-18* C-30

D-11 D-13 D-18 D-22 D-24 D-30

C-31 C33C-34 C-35 C-36 C-37

D-31 D-33 D-34 D-35 D-36 D-37

C-38 C-40

D-38 D-40

C-41 C-43

D-41 D-43

C-44 C-47 C-50 C-53 C-56

D-44 D-47 D-50 D-53 D-56

C-59 C-61 C-62 C-63 C-65 C-67 C-69* C-69* C-69* C-77

D-59 D-61 D-62 D-63 D-65 D-67

Subject to axial compression: Universal beam sections Universal column sections Joists Hot-finished circular hollow sections Hot-finished square hollow sections Hot-finished rectangular hollow sections Cold-formed circular hollow sections Cold-formed square hollow sections Cold-formed rectangular hollow sections Parallel flange channels subject to concentric axial compression Parallel flange channels connected through web Two parallel flange channels laced Two parallel flange channels back to back Equal angles Unequal angles - Short leg attached Unequal angles - Long leg attached Equal angles back to back: Connected to one side of gusset or member Connected to both sides of gusset or member Two unequal angles long legs back to back: Connected to one side of gusset or member Connected to both sides of gusset or member Subject to axial tension: Equal angles Unequal angles - Short leg attached Unequal angles - Long leg attached Two equal angles - Back to back Two unequal angles - Long legs back to back Subject to bending: Universal beams Universal columns Joists Hot-finished circular hollow sections Hot-finished square hollow sections Hot-finished rectangular hollow sections Cold-formed circular hollow sections Cold-formed square hollow sections Cold-formed rectangular hollow sections Parallel flange channels * Tables for grade S275, corresponding to tables in grade S355 do not exist. See notes on pages C-18 and C-69. x

D-69 D-72 D-74 D-77

Steel Grade S275 S355 Pink pages)

CD MEMBER CAPACITY TABLES

(Green pages)

Web bearing and buckling:

Universal beams Universal columns Joists Hot-finished square hollow sections Hot-finished rectangular hollow sections Cold-formed square hollow sections Cold-formed rectangular hollow sections Parallel flange channels

C-78 C-81 C-82 C-83 C-86 C-89* C-89* C-96

D-78 D-81 D-82 D-83 D-86 D-89 D-92 D-96

C-98 C-124 C-132 C-136 C-144 C-154 C-174* C-174* C-174* C-228

D-98 D-124 D-132 D-136 D-144 D-154 D-174 D-188 D-198 P-228

C-232 C-234 C-236 C-237 C-238 C-239

D-232 D-234 D-236 D-237 D-238 D-239

C-240

D-240

C-241

D-241

C-242 C-243

N/A

Subject to axial load and bending:

Universal beams Universal columns Joists Hot-finished circular hollow sections Hot-finished square hollow sections Hot-finished rectangular hollow sections Cold-formed circular hollow sections Cold-formed square hollow sections Cold-formed rectangular hollow sections Parallel flange channels Bolt capacities:

Non-preloaded ordinary bolts Non-preloaded countersunk bolts Non-preloaded HSFG bolts Preloaded HSFG bolts: Non-slip in service Preloaded HSFG bolts: Non-slip under factored loads Preloaded HSFG countersunk bolts: Non-slip in service Preloaded HSFG countersuck bolts: Non-slip under factored loads Weld capacities:

Fillet welds (Longitudinal and transverse) Floor plates:

Simply supported Encastre * Tables for grade S275, corresponding to tables in grade S355 do not exist. See notes on pages C-89 and C-174.

XI