UC project looking at impact of Wellington earthquake
UC summer project looking at impact of Wellington
earthquake building movements
November 17, 2013
A University of Canterbury (UC) summer research project is looking at the impact of building movements in the July and August Seddon earthquakes.
UC civil and natural resources engineer Dr Brendon Bradley says the project is vitally important as seismic response of buildings and other structures during earthquakes is highly complex with many assumptions made in conventional seismic design and assessment.
``Incorrect assumptions can be catastrophic due to excessive floor accelerations and building displacements. One of the principal means by which such assumptions can be assessed is by making use of the actual seismic response of buildings which have been ‘wired-up’ with instruments to measure their response during earthquakes.
``Several instrumented-buildings in Wellington were subjected to strong ground motions in the Seddon earthquakes. The aim of this project is to use signal processing analysis and simple structural analysis to assess common assumptions which are used in the design and assessment of structures.
``We will have a better understanding of the dynamics of the response of simple systems and how much buildings swayed in the magnitude 6.6 July and August Seddon earthquakes this year following our research.’’
Dr Bradley and UC summer scholarship student Ethan Thomson will research in the coming months to study the way in which Wellington buildings swayed in the earthquakes.
They will focus on 10 Wellington commercial and industrial buildings of different heights and construction styles.
The project will make use of buildings equipped with seismic instrumentation, which records building movement at multiple locations at the time the earthquakes occurred.
``The observed records will be used to scrutinise the accuracy of numerical models which are typically used in the design and assessment of structures for earthquakes. Based on an understanding of the limitations of conventional methods, improved procedures can be developed for use in the future. The pilot project will span about six months and results are expected in the first half of next year.’’
UC masters student Sam McHattie and Dr Bradley examined two buildings which were fixed with instruments before the 2010 and 2011 Canterbury earthquakes – the UC physics building and the CBD police station. Lessons learned from examining those buildings are also being up taken by the engineering profession.
Dr Bradley recently received $800,000 of a Rutherford Discovery Fellowship to investigate the mysteries of unresolved ground motion and geotechnical case histories from the 2010 and 2011 earthquakes. His research will have a national and international impact in the assessment and mitigation of earthquake hazards in major cities.
About 150 UC students will be undertaking scholarship research projects this summer. On top of that well over 700 students have enrolled in more than 80 summer courses.
Around 600 tradesmen will be on campus over the summer as the University’s building remediation programme ramps up.