THE MW 6.3 CHRISTCHURCH, NEW ZEALAND EARTHQUAKE OF 22 FEBRUARY 2011 A FIELD REPORT BY EEFIT THE CHRISTCHURCH, NEW ZEALAND EARTHQUAKE OF 22 FEBRUARY 2011 A FIELD REPORT BY EEFIT Sean Wilkinson Matthew Free Damian Grant David Boon Sarah Paganoni Anna Mason Elizabeth Williams Stuart Fraser Jenny Haskell Earthquake Field Investigation Team Institution of Structural Engineers 47 - 58 Bastwick Street London EC1V 3PS Tel 0207235 4535 Fax 0207235 4294 Email:
[email protected] June 2011 The Mw 6.2 Christchurch Earthquake of 22 February 2011 1 CONTENTS ACKNOWLEDGEMENTS 3 1. INTRODUCTION 4 2. REGIONAL TECTONIC AND GEOLOGICAL SETTING 6 3. SEISMOLOGICAL ASPECTS 12 4. NEW ZEALAND BUILDING STOCK AND DESIGN PRACTICE 25 5. PERFORMANCE OF BUILDINGS 32 6. PERFORMANCE OF LIFELINES 53 7. GEOTECHNICAL ASPECTS 62 8. DISASTER MANAGEMENT 96 9. ECONOMIC LOSSES AND INSURANCE 108 10. CONCLUSIONS 110 11. REFERENCES 112 APPENDIX A: DETAILED RESIDENTIAL DAMAGE SURVEY 117 The Mw 6.2 Christchurch Earthquake of 22 February 2011 2 ACKNOWLEDGEMENTS The authors would like to express their thanks to the many individuals and organisations that have assisted with the EEFIT mission to Christchurch and in the preparation of this report. We thank Arup for enabling Matthew Free to attend this mission and the British Geological Survey for allowing David Boon to attend. We would also like to thank the Engineering and Physical Sciences Research Council for providing funding for Sean Wilkinson, Damian Grant, Elizabeth Paganoni and Sarah Paganoni to join the team. Their continued support in enabling UK academics to witness the aftermath of earthquakes and the effects on structures and the communities they serve is gratefully acknowledged.