An engineer has heavily criticised the design of a building which collapsed during last year’s devastating Canterbury earthquake in New Zealand, killing more than 100 people.
According to a report on New Zealand website Stuff.co.nz, structural engineering professor Nigel Priestley has told the Canterbury earthquake’s royal commission that the design of the Canterbury Television (CTV) building was ‘undesirable’ and that the building’s key support wall, or shear wall, would ideally not be on the exterior.
“It’s quite clear that from a seismic point of view that this is an undesirable building configuration and [that makes it] very difficult to make it perform well [in earthquakes],” Priestly says.
Priestly also says it could not be known whether or not better steel reinforcement in the joints would have prevented the building from falling, but points out that theoretical tests suggests this could well be the case.
“I can’t say that the structure would have survived but I can say the…time-history analysis would not have predicted failure,” he says.
Priestly peer reviewed a report into the building’s collapse published by the Department of Building and Housing in February this year.
That report found that, along with intense ground shaking, a lack of ductility made the building’s columns brittle and the asymmetrical layout of the shear walls made them twist during the quake, placing further strain on the columns.
Crucially, the department’s report found that neither the ductility of the columns or layout of the shear walls met the building standards in place at the time the building was constructed.
Priestly dismissed assertions from another engineer, John Mander, who has described the building as ‘innovative’.
“It might be innovative but in a very undesirable sort of fashion,” Priestley says. “I cannot accept that this is an innovative structure in a desirable form for seismic resistance.”