Officials want to know why Bay Bridge bolts were chosen

May 22, 2013 12:00:00 AM PDT
There are new questions about the decision to use a certain kind of steel for thousands of bolts on the new Bay Bridge. Dozens have already cracked. They are the same kind of rods used on the Richmond-San Rafael Bridge. And now, a growing number of people want to know why and how they were chosen for the Bay Bridge.

UC Berkeley structural engineer Prof. Hassan Astaneh, Ph.D., claims Caltrans is downplaying the significance of its brittle bolt problem, so much so that it threatens the very integrity of the new eastern span of the Bay Bridge.

Astaneh says besides areas already identified, the potentially faulty bolts on the new span of the Bay Bridge are also holding together the saddle at the very top of the tower.

"If those bolts fail at the top of the tower, the entire cable will fall off the tower," Astaneh said. "The complete collapse of bridge is likely."

But Caltrans maintains that besides the 32 that snapped in March, the more than 2,000 similar bolts on the bridge have held up well, including those at the top of the tower.

"We are in the middle of ongoing testing of all similar bolts on all of the suspension bridge," Caltrans spokesperson Andrew Gordon told ABC7 News. "There's no evidence there is anything wrong."

"It really casts a cloud over Caltrans and the way they've handled this to date," Metropolitan Transportation Commissioner Tom Bates said.

In the meantime, Bates calls troubling new revelations about Caltrans decisions made more than a decade ago.

"The whole chain of events that led up to the fact that they said to go ahead and use these bolts really calls into question Caltrans' operation and the way they analyzed this and looked at it," Bates said.

Caltrans has released documents that reveal their engineers were persuaded by steel supplier Dyson Corporation to use the risky galvanized rods on the Bay Bridge.

A letter to the California legislature summarizes the documents, saying Caltrans decided on the Dyson bolts largely because the same type had been successfully installed on the Richmond-San Rafael Bridge.

On the Bay Bridge though, the bolts will be tightened to a level seven times greater than on the Richmond-San Rafael Bridge.

MTC Chairperson Amy Worth says whatever mistakes have been made by Caltrans in the past, the key now is to fix them and move on.

"As we have always said, the No. 1 priority is opening the bridge when it is safe and ready to do that," she said.

There is still no word on whether the bridge will be ready to open by Labor Day.


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