Lessons must be learned from Canterbury building failures
5 October 2011
New Zealand must apply lessons from investigations into Canterbury building failures, say earthquake engineers
Lessons from investigations into the failure of Christchurch buildings during the 22 February earthquake must be learned from, addressed and applied, says the New Zealand Society for Earthquake Engineering (NZSEE).
NZSEE executive officer Win Clark said that the society agreed with recommendations of the Department of Building and Housing’s technical investigation into the failure of the large multi-storey Pyne Gould Corporation (PGC), Forsyth Barr and Hotel Grand Chancellor buildings.
The DBH’s newly-released released reports from the investigations cite extremely strong ground shaking as one of principal reasons why the three buildings failed as well as noting that, at the time they were constructed, design requirements were less well understood than they are today.
The DBH has also released its report to the Minister for Building and Construction outlining its response to the findings, including urgent priority actions recommended by the expert panel that undertook the investigation.
Mr Clark said that the investigation has been extremely thorough, conducted by leading New Zealand expert engineering consultants whose findings were then peer reviewed by a panel including experts of international experience and standing. Over half are NZSEE members.
The reports will provide vital information to the Royal Commission of Inquiry into Building Failure Caused by Canterbury Earthquakes.
“One recommended priority action from the investigation is that lessons from the Canterbury earthquakes be incorporated into the Guidelines on the Assessment and Improvement of the Structural Performance of Buildings in Earthquakes,” said Mr Clark.
“These are published by the New Zealand Society for Earthquake Engineering and were updated in 2006, with the support of the Department, and have been used by most city and district councils and consultants in New Zealand when assessing their earthquake prone buildings and remedial actions as required by the Building Act.
“Before the September 2010 Darfield earthquake, the society was planning to update the guidelines using feedback from members and new research findings.
“The guidelines will now be updated to include findings from the DBH’s technical investigations and from the report by the Canterbury Earthquakes Royal Commission, expected next year, which will add further recommendations, relevant across New Zealand.”
Mr Clark said that NZSEE members have investigated significant earthquakes in New Zealand and from around the world for nearly 50 years, gaining vital knowledge which has improved New Zealand’s earthquake resilience.
“These investigations have resulted in improved building statutes, construction practices, and in establishing lifeline engineering, urban search and rescue (USAR), and the red, yellow and green building assessment procedures following an earthquake,” he said.
“Consequently while there was significant tragic loss of life from the earthquake of 22 February, we know from overseas examples that it was far less than it otherwise may have been.
“We owe it to those that lost their lives or suffered injury in Canterbury to identify the lessons for New Zealand from that tragedy through further investigation, research, and through the Royal Commission’s findings, and to learn from those lessons, address them and apply them with urgency.
“The New Zealand Society for Earthquake Engineering, working together with kindred professional societies (Structural Engineers, SESOC; Geotechnical Engineers, NZGS), IPENZ, and other relevant organisations and agencies, will continue its nearly five decades of active advocacy for the public of New Zealand, to drive progress and reduce risks from earthquakes.”