ISO INTERNATIONAL STANDARD 10721-1 First edition 1997-02-01 Steel structures - Part 1: Materials and design Structures en acier - Partie 1:Materiaux et conception This material is reproduced from Iso documents under International Organization for Standardization (Iso) Copyright License number IHS/lcC/1996.Notforresale.NopartoftheseISOdocumentsmaybe reproduced in any form, electronic retrieval system or otherwise, except as allowed in the copyright law of the country of use, or with the prior writtenconsentofIsO(Casepostale56,1211Geneva20,Switzerland,Fax +41 22 734 10 79), IHS or the Iso Licensor's members. So Reference number ISO 10721-1:1997(E) ISO 10721-1:1997(E) CONTENTS Page 1 SCOPE 2 NORMATIVEREFERENCES 3 DEFINITIONSAND SYMBOLS 2 3.1 Definitions 3.2 List of symbols 4 DOCUMENTATIONOFTHEDESIGN 11 4.1 Calculations 11 4.2 Testing 11 4.3 Documentation 11 5 BASIC DESIGN PRINCIPLES 11 5.1 Objectives and general recommendations 11 5.2 Limit states 12 5.3 Design situations and member resistance 12 5.3.1 General 12 5.3.2 Design situations 12 5.3.3 Member resistance 13 6 BASIC VARIABLES 13 6.1 General 13 6.2 Actions 13 6.2.1 General 13 6.2.2 Design value ............................................................. 14 6.3 Materials 14 6.3.1 General 14 6.3.2 Structural steels 14 6.3.3 Connecting devices 14 6.3.4 Testing and inspection of materials 15 6.4 Geometrical parameters 15 6.5 Design value of resistance 15 @ISO1997 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any fom or by any means, electronic or mechanical, including photocopying and microflm, without permission in writing from the publisher. InternationalOrganizationforStandardization Casepostale56.CH-1211Geneve20.Switzerland Internet [email protected] X.400 C=ch; a=400net; p=iso; 0=isocs; S=central Printed inSwitzerland i ISO 10721-1:1997(E) @ISO Page 7 ANALYSISOFSTRUCTURES 15 7.1 General 15 7.2 Structural behaviour 16 7.3 Methods of analysis 16 7.3.1 General 16 7.3.2 Elastic analysis 16 7.3.3 Elastic-plastic analysis 16 7.3.4 Plastic analysis 16 8 ULTIMATE LIMIT STATES 17 8.1 Member design 17 8.1.1 General 17 8.1.2 Cross-sectional resistance 17 8.1.3 Member stability 17 8.2 Resistance of members 18 8.2.1 Member strength 18 8.3 Classification of cross sections 18 8.3.1 General ... 18 8.3.2 Definitions of classes 18 8.3.3 Maximum width-thickness ratios of elements subjected to compression and/or bending 19 8.4 Flexural buckling 19 8.4.1 Effective buckling length 19 8.4.2 Slenderness 19 8.4.3 Compression resistance 20 8.4.4 Buckling strength f. 20 8.4.5 Compression members subjected to moments 20 8.4.6 Buckling of built-up members 8.5 Torsional and lateral torsional buckling 21 8.5.1 Torsional buckling 21 8.5.2 Lateral torsional buckling 21 8.5.3 Buckling strengths f. and f. 21 8.5.4 Bracing of beams, girders and trusses 22 8.6 Buckling of plates 22 8.6.1 General 22 8.6.2 Uniaxial force or in-plane moment 22 8.6.3 Shearresistanceofwebs 23 8.6.4 Combined forces 23 8.6.5 Webs or panels subdivided by stiffeners 23 ili ISO 10721-1:1997(E) @ISO Page 8.7 Connections, general reguirements 24 8.8 Bolted connections 25 8.8.1 General 25 8.8.2 Bolting details 25 8.8.3 Strength of connections with bolts and rivets 26 8.8.4 Slip coefficients 26 8.8.5 Deduction for holes 26 8.8.6 Length of connection .27 8.9 Welded connections 27 8.9.1 Scope 27 8.9.2 General requirements 28 8.9.3 Types of welds 29 8.9.4 Design assumptions 29 8.9.5 Designprovisions 30 8.9.6 Complete joint penetration groove welds in butt and tee joints 30 8.9.7 Fillet welds 32 8.9.8 Plug and slot welds 34 8.10 Joints in contact bearing 34 6 SERVICEABILITY LIMIT STATES 34 10 FATIGUE 35 10.1 Scope 35 10.1.1 General 35 10.1.2 Limitations 35 10.1.3 Situations in which no fatigue assessment is required 35 10.2 Fatigue assessment procedures 35 10.2.1 Fatigue assessment based on nominal stress range 36 10.2.2 Fatigue assessment based on a geometric stress range 10.3 F