Design of Floors for Vibration: A New Approach

1 SCI PUBLICATION P354 Design of Floors for Vibration: A New Approach (Revised Edition, February 2009) A L Smith BA MEng (Cantab) S J Hicks BEng PhD (Cantab) P J Devine BEng PgDip MSc CEng MICE Published by: The Steel Construction Institute Silwood Park Ascot Berkshire SL5 7QN Tel: 01344 636525 Fax: 01344 636570 P:\Pub\Pub800\Sign_off\P354\P354 with Jan 09 ii Printed 09/07/09 2007, 2009 The Steel Construction Institute Apart from any fair dealing for the purposes of research or private study or criticism or review, as permitted under theCopyright Designs and Patents Act, 1988, this publication may not be reproduced, stored or transmitted, in any form or byany means, without the prior permission in writing of the publishers, or in the case of reprographic reproduction only inaccordance 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.

2 Enquiries concerning reproduction outside the terms stated here should be sent to the publishers, The Steel Construction Institute, at the address given on the title page. Although care has been taken to ensure, to the best of our knowledge, that all data and information contained herein areaccurate to the extent that they relate to either matters of fact or accepted practice or matters of opinion at the time of publication, The Steel Construction Institute, the authors and the reviewers assume no responsibility for any errors in ormisinterpretations of such data and/or information or any loss or damage arising from or related to their use. Publications supplied to the Members of the Institute at a discount are not for resale by them. Publication Number: SCI P354 ISBN 10: 1-85942-176-8 ISBN 13: 978-1-85942-176-5 British Library Cataloguing-in-Publication Data.

3 A catalogue record for this book is available from the British Library. P:\Pub\Pub800\Sign_off\P354\P354 with Jan 09 iii Printed 09/07/09 FOREWORD Design guidance on the vibration of Floors was first published by The Steel Construction Institute in 1989, and related only to normal office building environments. It was prepared by Dr T A Wyatt of Imperial College London with assistance from Dr A F Dier of SCI. It has been widely used in practice and has stood the test of time. This new guidance document has been written to enable designers to determine the vibration response of sensitive Floors with improved accuracy. It will enable the response to be compared with BS 6472 and ISO 10137 for general structures, and with the specific NHS performance standard for hospitals, Health Technical Memorandum 08-01.

4 It includes Design guidance for all types of floor construction using steel members and for a variety of use characteristics. It makes reference to research and measurements in a variety of buildings that have demonstrated the good quality vibration performance that can be achieved with composite Floors . For composite Floors , the work leading to this publication was part-funded by Corus Construction Services & Development and by The European Coal and Steel Community through the project entitled Generalisation of criteria for floor vibrations for industrial, office, residential and public buildings and gymnastic halls (ECSC project PR7210-PR-314). The ECSC project was carried out by the following Partners: Rheinisch-Westf lische Technische Hochschule (RWTH) Aachen, Institute of Steel Construction (Project co-ordinator).

5 Arcelor Profil Luxembourg Research TNO Building and Construction Research The Steel Construction Institute (SCI) For lightweight Floors , the work was part-funded by Corus Strip Products UK and by the DTI Partners in Innovation project entitled Holistic assessment of the vibration sensitivity of lightweight Floors for various use patterns (DTI Reference: STBF/004/00053C CC2529). The DTI project was carried out by the following Partners: Atkins Design Environment and Engineering. Terrapin Metsec NHBC Corus Strip Products UK TRADA The Steel Construction Institute (SCI) The publication was prepared by Mr Andrew Smith, Dr Stephen Hicks and Mr Paul Devine of The Steel Construction Institute. The authors would also like to thank Professor Aleksandar Pavic and Professor Mark Lawson for their comments and advice on the publication, which are gratefully acknowledged.

6 Appendix C of the publication: Dynamic testing of building Floors was written by Professor Aleksandar Pavic and Dr Paul Reynolds, both of Sheffield University. This revised edition includes the latest advice on health buildings. Opportunity was taken to include the amendments given in corrigendum 1 and correct some typographical errors. The values in the worked examples have been adjusted in line with the corrigendum. P:\Pub\Pub800\Sign_off\P354\P354 with Jan 09 iv Printed 09/07/09 P:\Pub\Pub800\Sign_off\P354\P354 with Jan 09 v Printed 09/07/09 Contents Page No. FOREWORD iii SUMMARY vii NOTATION xi 1 INTRODUCTION 1 The vibration of Floors 1 Traditional approaches to Design 2 Scope of this guide 2 2 THEORY OF VIBRATION 4 Continuous and Discrete Systems 4 Frequency 5 Excitation 9 Response

7 10 3 SOURCES OF VIBRATIONS 14 Dynamic excitation forces 14 4 Design CONSIDERATIONS FOR Floors 20 Structural considerations 20 Architectural considerations 23 5 ACCEPTABILITY OF VIBRATIONS 25 Considerations 25 Human perception 25 Acceptance criteria 29 Sensitive Processes 32 6 GENERAL ASSESSMENT FOR ESTABLISHING VIBRATION RESPONSE 34 Finite element modelling (FE) 34 Modal mass 37 Response analysis 38 Summing accelerations 41 Acceptability criteria for continuous vibrations 42 Vibration dose values (VDVs) 44 Design process chart 45 7 SIMPLIFIED ASSESSMENT FOR STEEL Floors 46 Fundamental frequency 46 Minimum floor frequency 49 Modal Mass 49 Mode shape factor 52 Response acceleration 53 Acceptance criteria 54 8 SPECIAL CASES 56 Floors subject to rhythmic activities 56 Hospital Floors 58 Light steel Floors 60 Car parks 65 P.

8 \Pub\Pub800\Sign_off\P354\P354 with Jan 09 vi Printed 09/07/09 9 REFERENCES 67 APPENDIX A Comparison of analysis methods with measurements 73 Test procedures 73 Results from testing office Floors 73 Results from testing hospital Floors 74 Comparison of predictions with measurements 76 Lightweight Floors 78 APPENDIX B Retrofit and remedial strategies 80 Evaluation of floor vibration problems 80 Retrofit and remedial measures for Steel-concrete construction 81 Retrofit strategies for machine induced vibrations 82 APPENDIX C Dynamic testing of building Floors 84 Modal testing 84 Modal testing of Floors with measurements made of the excitation force 86 Vibration performance assessment 91 Management issues 95 APPENDIX D Worked Examples 97 Vibration response of a composite floor 98 Vibration response of a lightweight floor 106 Design for rhythmic activity 112 P:\Pub\Pub800\Sign_off\P354\P354 with Jan 09 vii Printed 09/07/09 SUMMARY This publication provides guidance for vibration Design of all steel-framed floor and building types.

9 It deals with the human perception of vibration and the criteria by which it is measured. The concepts of floor response and the different types of excitation produced by occupant induced vibrations are explained. Simple Design procedures are presented which show how to calculate the floor acceleration, to weight it to reflect human perception, and to compare it with the acceptance levels in BS 6472 and ISO 10137 for building designs and in the NHS performance standard for hospitals, Health Technical Memorandum 08-01. The Design procedures are valid for steel-framed Floors using hot rolled steel sections and lightweight Floors using thin cold formed steel members. The simplified procedure is particularly suited to framing arrangements that are generally regular in plan.

10 Results from testing which have been used to develop the rules contained within this guide have been included in Appendix A. Additional information on managing problems in a remedial situation is given in Appendix B. Specialist guidance on dynamic testing of buildings is provided in Appendix C; this has been specially written by Professor Aleksander Pavic and Dr Paul Reynolds, both of Sheffield University. A set of worked examples, illustrating the Design procedures is given in Appendix D. Dimensionnement des planchers par rapport aux vibrations : une nouvelle approche R sum Cette publication est destin e servir de guide de dimensionnement concernant les vibrations de tout type de planchers reposant sur une ossature en acier, pour tout type de b timents.