By JASON DEAREN and SUDHIN THANAWALA, Associated Press Writers
SAN FRANCISCO – San Francisco Bay area commuters were bracing for another day of wearisome commutes as crews worked on repairs to the San Francisco-Oakland Bay Bridge.
A day after 5,000 pounds of metal fell and hit the San Francisco-Oakland Bay Bridge during an evening rush hour, state transportation officials said the bridge would not open in time for the Thursday morning commute.
There is no estimate for when the bridge will open again as crews were scheduled to work through the night and morning.
The pieces that failed Tuesday were parts of major repairs done last month after state inspectors discovered a crack in an "eyebar," an important structural beam. The rods that broke were holding a saddle-like cap that had been installed to strengthen the cracked eyebar. Only motorist was left with minor injuries after the incident Tuesday.
Officials with the California Department of Transportation attributed the incident to vibrations and grinding on a metal tie rod, causing it to snap.
During a briefing Wednesday, state transportation spokesman Bart Ney said crews were "making several enhancements to address that issue."
He also said strong winds likely played a role in the failure, which heightened concerns by some experts about the integrity of the repair and the bridge's safety in an earthquake. Scientists in 2008 said there is a 63 percent probability of a quake similar to the 6.9-magnitude Loma Prieta temblor in the Bay area over the next 30 years.
The 1989 earthquake caused a 50-foot section of the bridge's upper deck to collapse onto the deck below, causing another section to give way.
It took state officials until 1997 to decide it would be cheaper over the long run to build a new span than retrofit the existing one.
Transit officials said Wednesday that many of the estimated 280,000 commuters that use the bridge every day jammed alternate routes and crowded into buses and trains as they tried to get into San Francisco.
Officials with the Bay Area Rapid Transit District said it saw an increase in ridership of nearly 56,000 passengers, or about 49 percent, Wednesday between the East Bay and San Francisco. BART added extra cars to its trains in anticipation of the increase in riders.
Drivers using the other bridges across San Francisco Bay are expected to face delays again as they jam bridges for a second day Thursday.
The westbound drive across the San Mateo Bridge, which typically takes about 15 minutes, was a 50-minute drive Wednesday morning. Traffic on the bridge was about 40 percent heavier than usual, according to a bridge supervisor.
Traffic is also expected to be heavier on the Golden Gate Bridge for a second day in a row.
Abolhassan Astaneh-Asl, a civil engineering professor at the University of California, Berkeley who studied the effects of the 1989 earthquake on the bridge, called the repair last month a "Band-Aid" that jeopardized public safety to get the bridge open quickly.
"When this eyebar fractured, this is very serious element of this part of the bridge. So the safety issue is very serious here," he said. "The repair done, in my opinion, is very unusual to put it mildly."
The main contractor on the repairs, C.C. Meyers, Inc., stood by the work, but deferred to Caltrans to determine why the pieces failed, spokeswoman Beth Ruyak said.
Meanwhile, the Federal Highway Administration sent engineers on Wednesday to help Caltrans investigate. The federal agency said it had not inspected the Labor Day weekend repairs made to the heavily used span, instead relying on state inspection reports to ensure safety guidelines were met.
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