More than 400 seismic safety rods that may be vulnerable to cracking or breaking are embedded in the base of the new San Francisco-Oakland Bay Bridge and may be difficult to inspect, remove or replace, according to a newspaper report.
The 424 threaded rods are among more than 2,000 on the $6.4 billion span that the California Department of Transportation recently realized are vulnerable to being invaded by hydrogen. That could cause them to become brittle, the San Francisco Chronicle reported Saturday.
``These are going to get added scrutiny,'' Caltrans spokesman Will Shuck told the newspaper. ``We're going to make 100 percent sure they are safe.''
The rods are intended to counter the swaying forces on the tower during an earthquake. Caltrans officials said the rods are not being subjected to a high stress load, which they say reduces the risk they could crack.
The high-strength steel rods were galvanized under conditions Caltrans barred as putting them at risk of cracking, the Chronicle said. Federal and state highway officials have long warned against galvanizing such high-strength steel and using it on bridges because of the possibility it will fail.
Caltrans said last week that the planned repair for broken seismic safety rods on the new span of the new Bay Bridge could cost between $5 million and $10 million.
Officials still don't know whether the repair will be done in time for the span's scheduled Labor Day opening, but they say it's still possible. A decision is expected May 29.