OAKLAND (KCBS) – Documents released on Tuesday show that Caltrans was persuaded to use questionable bolts on the Bay Bridge, after a supplier pointed out that they were already in use at the Richmond-San Rafael Bridge.
But experts said the bolts don’t perform the same function on each bridge. On the Richmond-San Rafael Bridge, the galvanized steel rods were tightened to lower tension levels, seven times lower than those on the Bay Bridge.
It was those higher tension levels that contributed to 32 rods cracking on the new eastern span.
The Caltrans emails show the Dyson Corp., a major supplier of rods for both projects, sent a fax in March of 2003 pointing out that despite initial concerns abut the integrity of the material, Caltrans had already approved them for use on the Richmond-San Rafael Bridge.
Last week, Caltrans Director Malcolm Dougherty told a state Senate Committee that the agency knew at the time what the potential risks for the rods were prior to installation.
“We were using industry standards and it was a decision that was made eyes wide open,” he said. “It had been done before and used before and used successfully.”
Caltrans is now testing several of the questionable rods from the Bay Bridge.
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