EARTHQUAKE ENGINEERING EST BRITAIN 1 Proceedings of a conference organized by the Institution of Civil Engineers and the Society of Earthquake and Civil Engineering Dynamics, held at the University of East Anglia 18-19 f April 1985. EARTHQUAKE ENGINEERING IN BRITAIN I Thomas Telford, London Conference organized by the Institution of Civil Engineers in association with the Society for Earthquake and Civil Engineer ing Dynamics, held at the University of East Anglia, 18-19 April 1985. \ Organizing Committee Mr. D. E. Key, Chairman, Society for Earthquake and Civil Engineering Dynamics Dr B. O. Skipp, Soil Mechanics Limited (Chairman) Dr R R Kunar, Structural Dynamics Research Corporation Dr D. Papastamatiou, Delta Pi Associates Cataloguing in Publication Data Earthquake Engineering in Britain: proceedings of a conference organized by the Institution of Civil Engineers and the Society of Earthquake and Civil Engineering Dynamics held at the University of East Anglia, 18-19 April 1985. 1. Earthquake engineering— Great Britain. I. Institution of Civil Engineers. II. Society of Earthquake and Civil Engineering Dynamics. 624.1762'0941 TA654.6 ISBN 0 7277 0246 7 First published 1985 @ Institution of Civil Engineers 1985 unless otherwise stated All rights, including translation, reserved. Except for fair copying, no part of this publication may be reproduced, stored in a retrieval system, or transmitted in any othe£ form or by any means electronic, mechanical, photocopying, recording or otherwise, without the prior written permis sion of the Publications Manager, Thomas Telford Ltd, 26-34 Old Street, London EC1P1IH Papers or other contributions and the statements made or opinions expressed therein are published on the understanding that the author of the contribution is solely responsible for the opinions expressed in it and that its publication does not necessarily imply that such statements and or opinions are or reflect the views or opinions of ICE Council or ICE committees Published for the Institution of Civil Engineers by Thomas Telford Ltd, 26-34 Old Street, PO Box 101, London EC1P1JH Printed in Great Britain by Billing and Sons, Worcester Contents Keynote Address. D. KEY 1 Earthquake activity in Britain ? 1. The geography and intensity of earthquakes in Britain - the eighteenth century. C. P. MELVILLE 7 y 2. ISC Records of British earthquakes. R. D.ADAMS 25 £/ 3. Investigation of British earthquakes using the national monitoring network of the British Geological Survey. C. W. A. BROWITT, T. TURBITT and S. N. MORGAN 33 ^ 4. Long-term seismicity in Britain. N. M. AMBRASEYS and J. A. JACKSON 49 5. Event triggered seismic detection systems developed by the British Geological Survey. D. J. HOULISTON, J. LAUGHUN and G. WAUGH 67 6. Instrumental magnitudes of British earthquakes. G. NEILSON and P. W. BURTON 83 * 7. A comparison of two historical earthquakes in North Wales. R. M. W. MUSSON, G. NEILSON and P. W. BURTON 87 8. Macroseismic focal depth and intensity attenuation for British earthquakes. P. W. BURTON, R. McGONIGLE, G. NEILSON and R M. W. MUSSON 91 9. Seismicity associated with Longwall coal mining. N. J. KUSZNIR, T. G. BLENKINSOP, R. E. LONG and M. J.SMITH 111 10. The Seismotectonics of North-West Europe. R.MUIRWOOD 129 £ 11. Fault activity and palaeoseismicity during quaternary time in Scotland — preliminary studies. C A. DAVENPORT and P. S. RINGROSE 143 12. Satellite imagery applied to investigations of geological structured as part of recent seismic hazard studies in the UK. J. C. GUTMANIS, R W. HOLT and R A. WHITTLE 157 * 13. A ground motion probability analysis for Britain based on macroseismic earthquake data. R E. LONG 169 >14. Seismic ground motions in Great Britain. G. WOO 183 15. Colchester revisited. B. O. SKIPP, D. T. SHILSTON, J. C. GUTMANIS and R D. ADAMS 189 16. The 8 November earthquake at Liege, Belgium. W. P. ASPINALL 207 17. On the seismicity of the south-west of the British Isles. J. M. MENU, N. N. AMBRASEYS and C. P. MELVILLE 227 Seismic engineering 18. Seismic engineering requirements in British industry. M. A. H. G. ALDERSON 243 19. Earthquake hazard in Britain. J. IRVING 261 20. Promises and limitations of available techniques in UK seismotectonic investigations. D. PAPASTAMATIOU 279 21. Methods of seismic qualifications for hazardous facilities in the UK. R R KUNAR 293 22. Seismic design approach for the Sizewell 'B' nuclear power plant. C. R. SMITH 305 23. Response to extreme earthquakes of an offshore concrete gravity platform in the North Sea. E. D. BOOTH and C. J. B. ROBERTS 321 24. The aseismic design of a reactor building for the advanced gas cooled reactor power plant. D. C. PAL and J.V.PARKER 335 25. Seismic analysis of the Upper and Lower Glendevon dams C. A. TAYLOR A. A. DUMANOGLU, J. TREVELYAN, J. R. MAGUIRE, R. T. SEVERN and A. G ALLEN 351 26. Probability of seismically induced liquefaction in British sector of North Sea. W. D. LIAM FINN and GAIL M. ATKINSON 365 Open discussion Presentations and discussion 379 Panel discussion 385 KEYNOTE ADDRESS D. KEY, Chairman, Society for Earthquake and Civil Engineering Dynamics On behalf of the members and committee of SECED I welcome all those participating in the conference to the University of East Anglia. To introduce the reasons for having this conference it is first necessary to introduce, to many of you, the Society for Earthquake and Civil Engineering Dynamics, SECED. SECED operates under the aegis of the Institution of Civil Engineers and is the British National Section of the International Association for Earthquake Engineering, IAEE. The function of SECED is to promote co-operation and the advancement of knowledge in its field, in pursuance of which it holds meetings and conferences for discussion and publishes papers and reports. It provides a medium for co operation between industry and research and a channel through which the many specialists concerned in earthquakes and dynamics can express their views - as was recently done on Eurocode 8 (the European Code for Structures in Seismic Regions). It is also Earthquake Engineering in Britain. Thomas Telford Ltd, London, 1985 1 EARTHQUAKE ENGINEERING IN BRITAIN publishing the first directory of services available in the fields of earthquake engineering and dynamics, and has recently undertaken a role in conjunction with the Science and Engineering Research Council to act as a link between industry and research. Membership of SECED covers a wide range of disciplines, including geologists, seismologists, engineering seismologists, civil, structural, mechanical and soils engineers. Membership is open to all those engaged in relevant disciplines and is not limited to members of the Institution of Civil Engineers. Attendance at meeting is open to members and non members alike. The conference subject is at the interface between two important areas of activity in Britain. Both British earthquake engineering and British seismology are concerned with their discipline world wide. It is a well known fact that, in Britain, we do not have earthquakes, and like most "well known facts" this is not true. However it is true to say that the level of seismicity in Britain is low. The reason for bringing engineers and seismologists together at this conference is the growing realisation, that, for many classes of civil engineering structures, where the acceptable risk of failure is very small, even the low level of British seismicity is a matter of serious concern to the engineer. Such structures include nuclear installations, manufacturing or storage facilities for dangerous chemicals, dams, long span bridges, power stations and off-shore platforms. Within these fields there is a great deal of 2