Widow tells of pressure on engineer
The owner of the company that designed the CTV building put pressure on a Christchurch City Council boss to have his building consents approved, it was alleged yesterday.
The Canterbury Earthquakes Royal Commission was told that Alan Reay, principal of Alan Reay Consultants Ltd, would ring the manager of the council building engineers team throughout the 1980s and 1990s over problems with getting his designs approved.
Graeme Tapper, who is now dead, signed off the Canterbury Television design in 1986.
His widow, Pat Tapper, told the commission that he did so only because he was worried about his job. She said her husband never talked about work at home, but the CTV building was "the one exception".
"Graeme went on and on about the CTV building," Tapper said.
"His view was that there were earthquake risks. It was not a question of if, but when.
"He was concerned the CTV building would not prove to be strong enough."
She said her husband did not want to sign off the CTV building but was under "huge pressure" from his boss, Bryan Bluck (also now dead), and was concerned about his job.
Engineer John Henry worked with Tapper and Bluck at the council in the 1990s. Bluck was chief building engineer and Tapper was assistant building engineer.
Henry told the commission that Tapper regularly took issue with the design of buildings by Alan Reay Consultants, where Henry also worked, in 1984-1985.
Henry said it was not uncommon for Reay to go directly to Bluck when issues arose over Tapper not issuing consents.
Bluck and Tapper would then have "extreme" arguments about technical issues in the designs.
Tapper, who was unwell because of a heart condition, would sometimes have to take a break after these arguments to recover, Henry said.
He said there was "big pressure" to get consents through and Tapper was "ultimately over-ruled" by Bluck.
"I think Graeme Tapper worked consistently with that principle, except when he knew darn right he had a situation he couldn't live with," Henry said.
Tapper asked in a letter to Alan Reay Consultants in August 1986 for more detail about the CTV design because he had identified issues about floor connections. Henry said Tapper would often write letters if he feared being over-ruled by Bluck.
"He would often say he wanted to leave a paper trail."
Henry said Bluck did not have sufficient understanding of the technical matters involved to be able to confidently support Tapper.
CTV MODEL 'MISMATCHED'
The Canterbury Television building and the high rise it was modelled on were "substantially mismatched" in strength and stiffness, an inquiry has heard.
Structural engineer John Henry told the Canterbury Earthquakes Royal Commission yesterday that he was concerned to learn that calculations for Landsborough House were used as a template for the CTV design.
He said his calculations would be clear only to an experienced designer, but the engineer who used them, David Harding, had not worked on a high rise before.
Henry designed Landsborough House, on the corner of Durham and Gloucester streets, while working for Alan Reay Consultants in 1985.
Harding replaced him and did the detailed design of the CTV building in 1986.
Using models, Henry showed the commission how the corners of Landsborough House were connected. That was crucial to its ability to withstand an earthquake. In the CTV design, the corners were not attached.
Henry outlined how the vertical north core, the main support in a building, was inside the frame of Landsborough House.
The building would twist around the north core in a quake.
In the CTV design, the north core was on the outside of the main frame.
To compensate, there was a small coupled shear wall on the south side. Henry said that was "not enough". The building would still be vulnerable. Effectively, the north wall of the CTV building was the only main support.
It was not until late last year that Henry learnt from Harding that Landsborough House was used a guide for the CTV job.
Henry said if he had known that was going to happen in 1985, he would have included more detailed explanations in his notes.
However, anyone using them would still need direction.
Harding failed to test the strengths of the corners of the CTV building because he did not know he needed to.
He said in earlier evidence that he was relying on guidance from his boss, Alan Reay. Reay denies having any involvement.
Landsborough House stood up in the February 2011 quake, but is listed for demolition.
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