Editorial: How many problems plague Bay Bridge? Let us count the ways
05/02/2013 12:00 AM
04/12/2014 7:36 PM
Fundraising for the opening bash planned for the new San Francisco-Oakland Bay Bridge – scheduled for the Labor Day weekend – has been suspended. That's the clearest indication yet that the new span's cracked bolts and other problems pose serious risks to a safe opening of this bridge.
As The Bee's Charles Piller reported several weeks ago, 32 of 96 giant bolts used to support seismic safety equipment cracked when tightened in March. That's a failure rate of more than 30 percent, alarming to say the least.
Then over the weekend, the San Francisco Chronicle reported that the Bay Bridge's new eastern span has more than 1,200 bolts made, like the bolts that cracked, from a type of galvanized steel that a nationwide group of transportation officials banned from bridge use because it was susceptible to cracking over time.
The bolts are coated with a zinc material that is intended to keep them from rusting. But zinc can react with hydrogen found in rainwater and fog, causing an electro-chemical reaction that makes hardened steel brittle, and thus susceptible to cracking.
Incredibly, Caltrans' own bridge design manual forbids the use of the type of steel rods in question. Caltrans officials told the Chronicle that the Bay Bridge had different project-specific criteria and that the manual's "generic specifications are for run-of-the-mill-bridges, and this bridge is not run-of-the-mill."
Experts in the field contacted by the Chronicle expressed shock.
"This is completely the wrong material for use in this application," one said. "Irresponsible," another called the state's actions in using the type of bolts it did.
The suspect bolts play a vital role in bridge safety. Engineers say they anchor structures that are supposed to keep the bridge stable in an earthquake, banding the main cables together and binding them to the road decks.
Caltrans officials are scrambling to find out what went wrong, assess how serious the problem is and engineer a fix. In the past they've said it would not delay the bridge's Sept. 3 opening but that now is highly doubtful.
Cracked bolts are just the latest of a string of construction mishaps that have plagued the rebuilding of the $6.4 billion eastern span of the Bay Bridge.
Previously, Piller broke the story about a Caltrans employee who ignored proper procedures for testing structural integrity of concrete in the bridge's tower foundations. Inspectors have also found microscopic cracks in steel deck sections fabricated in China.
On Wednesday, Piller reported Caltrans is working with contractors to fix defects on portions of 20 welds – each nearly 33 feet long and up to 4 inches thick – on the tower of the new bridge.
It is vital for Caltrans to open the new span as quickly as possible, since the old one remains highly vulnerable to an earthquake, which could occur any day. But the bridge must be safe upon opening.
Revelations of cracked bolts and other problems raise urgent questions about the integrity of the bridge, one of the nation's largest public works projects, and the competence of Caltrans to manage its construction. Legislators have scheduled a May 14 hearing to discuss the issue. Caltrans officials will face some very hard grilling, rightfully so.
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