The old Bay Bridge and the new route bridge can be seen side by side.
In this frame from video provided by Caltrans, construction workers place a buckle over a cracked eyebar on the eastern portion of the Bay Bridge on Monday, September 7, 2009. Repairs continue on a portion of the San Francisco-Oakland Bay Bridge for Labor Day weekend beginning Thursday, September 3, 2009.
Workers on the eastern span of the Bay Bridge reinforce a cracked eyebar discovered while the bridge was closed.
California Transportation Department workers survey a cracked steel link, called an eyebar, that helps hold up the Bay Bridge's east span. Sept 7, 2009.
Saddle is installed to distribute the weight to the rest of the eyebars and prevent further widening of the crack , can be seen just below the saddle.
Location of the crack and the saddle with the tie beams.
A replacement section slides into place connecting the new detour route during the San Francisco-Oakland Bay Bridge seismic retrofit in San Francisco, Saturday, Sept. 5, 2009. The bridge is closed over the Labor Day weekend and expected to reopen before morning rush hour Tuesday.
Click the image above to inlarge image. Show the replacement re route bridge and segment.
The crack can be seen , right of below one of the eye beam of the Bay Bridge. The crack give an sufficient worries to the engineers.
The Bay Bridge will remain closed until at least Wednesday morning as crews work nonstop to repair what's been described as a "significant" crack in the bridge's east span near Yerba Buena Island.
The bridge had been shut in both directions since Thursday night as part of a major seismic project, and had been expected to reopen for today's morning commute.
However, the surprise discovery Saturday of a large crack in a steel beam forced emergency repairs requiring the bridge to remain closed.
"We know this is going to be a major inconvenience for Bay Area commuters, but this should not overshadow the tremendous work that was completed this weekend," Caltrans Director Randell Iwasaki said.
The bridge is the most heavily used in the state, typically handling 248,000 vehicles a day, Caltrans officials said.
Bay Area officials made a point of saying workers and other travelers should be able to get into San Francisco.
"Our advice is to take transit and be patient," Goodwin said. "You'll get there. The city is open for business."
The bridge had been closed through the Labor Day weekend to allow crews to cut away a 300-foot section of the bridge and slide a new section into its place, at an angle, linking to a new detour route at Yerba Buena Island.
State bridge inspectors on Saturday found a significant crack halfway through a 2-inch-thick beam called an eyebar on the bridge's cantilever section. An eyebar is a straight bar with a hole at each end connecting to other bridge parts.
The crack was not related to the weekend work, officials said, and appears to have occurred since a 2007 inspection. Officials said the crack was serious enough to have required a bridge closure had the bridge not already been closed for the seismic project.
"We are fortunate this was discovered when so many experienced contractors and skilled workers were on the scene, able to respond immediately," said Bob Alvarado of the California Transportation Commission.
Support pieces were rush-ordered Saturday from an Arizona company. The pieces were manufactured and sent to the Bay Area on Sunday.
"This repair had to be designed on the fly," Goodwin said. "They are having to fit the pieces together."
The stress load at that section of the bridge had been taken up safely by seven similar beams, officials said, but the damaged beam needs to be fixed. The repair essentially involves placing a metal splint around the broken piece.
Caltrans officials warned drivers that when the bridge reopens, speed limits at Yerba Buena Island will be reduced from 50 to 40 mph to accommodate two turns on the detour route.
Those two turns allow space for construction crews to build the new bridge directly toward the island's tunnel.
Unlike the existing east span, which is a double-deck bridge, the new bridge will be a set of side-by-side bridges, and will include a single suspension tower.
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