Caltrans Was Warned Bay Bridge Welds Could Crack
The firm that designed the new Bay Bridge eastern span warned Caltrans as the bridge neared completion that some of its welds could crack prematurely under the constant pounding of cars and trucks, The Chronicle has learned.
The potential for cracking was created after the span was designed, said engineers with the firm T.Y. Lin International. It happened when Caltrans suspended its rules and allowed the bridge builder to weld together Chinese-manufactured sections of steel road deck that didn’t fit together correctly.
Any cracks in the welded connections would be minor, the engineers concluded, and would not pose the threat of a catastrophic failure. However, such cracking could shorten the time before toll-payer dollars would be needed to make repairs to the $6.4 billion bridge.
The engineers also told Caltrans and other bridge project officials that in a major earthquake there would likely be some damage to the ill-fitting joints.
In their November 2010 evaluation, the T.Y. Lin engineers identified a section of the eastbound deck near Yerba Buena Island as being of particular concern, because lopsided welded connections are under high stress and thus are especially vulnerable to premature cracking. The Chronicle obtained the firm’s report under the state Public Records Act.
Nothing like waiting years for a safe alternative to the old bridge only to find out that the expensive and beautiful new span may have even more problems than the previous span.