Design aids for EC2 JOIN US ON THE INTERNET VIA WWW, GOPHER, FTP OR EMAIL: www: http://www.thomson.com A service of GOPHER: gopher.thomson.com FTP: ftp.thomson.com EMAIL: [email protected] Design aids for EC2 Design of concrete structures Design aids for ENV 1992–1–1 Eurocode 2, part 1 Betonvereniging The Concrete Society Deutscher Beton-Verein E & FN SPON An Imprint of Chapman & Hall London · Weinheim · New York · Tokyo · Melbourne · Madras Published by E & FN Spon, an imprint of Chapman & Hall, 2–6 Boundary Row, London SE1 8HN, UK Chapman & Hall, 2–6 Boundary Row, London SE1 8HN, UK Chapman & Hall GmbH, Pappelallee 3, 69469 Weinheim, Germany Chapman & Hall USA, 115 Fifth Avenue, New York, NY 10003, USA Chapman & Hall Japan, ITP-Japan, Kyowa Building, 3F, 2–2–1 Hirakawacho, Chiyoda-ku, Tokyo 102, Japan DA Book (Aust.) Pty Ltd, 648 Whitehorse Road, Mitcham 3132, Victoria, Australia Chapman & Hall India, R.Seshadri, 32 Second Main Road, CIT East, Madras 600 035, India First edition 1997 This edition published in the Taylor & Francis e-Library, 2005. “To purchase your own copy of this or any of Taylor & Francis or Routledge’s collection of thousands of eBooks please go to www.eBookstore.tandf.co.uk.” © 1997 Betonvereniging, The Concrete Society and Deutscher Beton-Verein ISBN 0-203-47639-5 Master e-book ISBN ISBN 0-203-78463-4 (Adobe eReader Format) ISBN 0 419 21190 X (Print Edition) Apart from any fair dealing for the purposes of research or private study, or criticism or review, as permitted under the UK 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 Copyright Licensing Agency in the UK, or in accordance with the terms of licences issued by the appropriate Reproduction Rights Organization outside the UK. 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Contents Preface 1 1 General information 2 1.1 Construction products directive and European harmonized standards for concrete structures 1.2 Future European code of practice for concrete structures 1.3 Safety concept relevant to any type of construction material 1.4 Eurocode 2 for the design and execution of concrete structures 1.4.1 General 1.4.2 Contents of Eurocode 2: principles and application rules: indicative numerical values 1.4.3 Essential requirements for design and execution 1.5 References 2 Mains symbols used in EC2 7 3 Overview of flow charts 12 4 Design requirements 40 4.1 Combinations of actions 4.2 Categories and values of imposed loads 4.3 (cid:0)Ψ factors (Eurocode 1, part 2.1 (ENV 1991–2–1)) 4.4 Partial safety factors for actions 4.5 Partial safety factors for materials 5 Calculation methods 46 5.1 Flat slabs 5.1.1 Introduction 5.1.2 Equivalent frame method 5.1.3 Use of simplified coefficients 5.1.4 Reinforcement 5.2 Strut-and-tie methods 6 Material properties 50 6.1 Concrete 6.2 Reinforcing steel 6.3 Prestressing steel 7 Basic design 53 7.1 Exposure classes 7.2 Minimum cover requirements for normal weight concrete vi 7.3 Durability requirements related to environmental exposure 7.4 Strength classes to satisfy maximum water/cement ratio requirements 7.5 Prestressed concrete 7.5.1 Material properties 7.5.2 Minimum number of tendons 7.5.3 Initial prestressing force 7.5.4 Loss of prestress 7.5.5 Anchorage 8 Bending and longitudinal force 59 8.1 Conditions at failure 8.2 Design of rectangular sections subject to flexure only 8.3 Flanged beams 8.4 Minimum reinforcement 8.5 Design charts for columns (combined axial and bending) 9 Shear and torsion 95 9.1 Shear 9.1.1 General 9.1.2 V /b d Rd1 w 9.1. 3a Standard method V /b d Rd2 w 9.1.3 b Variable strut inclination method V /b d Rd2 w 9.1.4 V . /V Rd2red Rd2 9.1.5 V /d and V /d wd Rd3 9.2 Torsion 9.2.1 General 9.2.2 T /h3 Rd2 9.2. 3a T /h2 Rd2 9.2.3b T /h2 Rd2 9.2. 3c T /h2 Rd2 9.2. 3c T /h3 Rd2 9.3 Combination of torsion and shear 10 Punching 107 10.1 General 10.2a V /d for circular loaded areas Sd vii 10.2b V /d for rectangular loaded areas Sd 10.3 V /d Rd1 10.4a V /d–V /d Rd3 Rd1 10.4b V /d–V /d rectangular loaded areas Rd3 Rd1 11 Elements with second order effects 115 11.1 Determination of effective length of columns 12 Control of cracking 119 13 Deflections 127 13.1 General 13.2 Ratios of span to effective depth 13.3 Calculation of deflection 14 Detailing 131 14.1 Bond conditions 14.2 Anchorage and lap lengths 14.3 Transverse reinforcement 14.4 Curtailment of bars in flexural members 15 Numerical examples designed to ENV 1992–1–1 135 15.1 Introduction 15.2 References 15.3 Calculation for an office building 15.3.1 Floor plan, structural details and basic data 15.3. 1.1 Floor plan of an office building 15.3. 1.2 Structural details of an office building 15.3. 1.3 Basic data of structure, materials and loading 15.3.2 Calculation of a flat slab 15.3. 2.1 Actions 15.3. 2.2 Structural model at the ultimate limit states (finite element grid) 15.3. 2.3 Design values of bending moments (example) 15.3. 2.4 Design of bending at the ultimate limit states 15.3. 2.5 Ultimate limit state for punching shear viii 15.3.2 .6 Limitation of deflections 15.3. 3 Internal column 15.3. 4 Facade element 15.3. 5 Block foundation 15.4 Calculation for a residential building 15.4.1 .2 Basic data of structure, materials and loading 15.4. 2 Continuous slab (end span) 15.4.2 .1 Floor span and idealization of the structure 15.4.2 .2 Limitation of deflections 15.4.2 .3 Actions 15.4.2 .4 Structural analysis 15.4.2 .5 Design at ultimate limit states for bending and axial force 15.4.2 .6 Design for shear 15.4.2 .7 Minimum reinforcement for crack control 15.4.2 .8 Detailing of reinforcement 15.4. 3 Continuous edge beam (end span) 15.4.3 .1 Structural system 15.4.3 .2 Actions 15.4.3 .3 Structural analysis 15.4.3 .4 Design of span 1 for bending 15.4.3 .5 Design for shear 15.4.3 .6 Control of cracking 15.4.3 .7 Detailing of reinforcement ix 15.4. 4 Braced tranverse frame in axis E 15.4. 4.1 Structural system; cross-sectional dimensions 15.4. 4.2 Actions 15.4. 4.3 Structural analysis 15.4. 4.4 Design for the ultimate limit states 15.5. 1 Floor plan; elevation 15.5. 2 Calculation of prestressed concrete beam 15.5. 2.1 Basic data 15.5. 2.2 Actions 15.5. 2.3 Action effects due to G G and Q k,19 k,2 k 15.5. 2.4 Action effects due to prestress 15.5. 2.5 Design for the ultimate limit states for bending and longitudinal force 15.5. 2.6 Design for shear 15.5. 3 Calculation of edge column subjected to crane-induced actions 15.5. 3.1 Basic data and design value of actions 15.5. 3.2 Design values of actions 15.5. 3.3 Design of the column for the ultimate limit states induced by structural deformations 15.5. 3.4 Designs of the column; detailing of reinforcement 15.5. 3.5 Ultimate limit state of fatigue 15.6 Guidance for the calculation of the equivalent stress range (cid:0) (cid:0) for reinforcing steel and of the S-N curve for s,equ concrete and of the S-N curve for concrete in compression using the single load level method 15.6. 1 Reinforcing steel 15.6. 2 Concrete