Panel suggests fixes for Bay Bridge tower rods
A panel of experts convened to determine the extent of water damage to anchor rods in the base of the Bay Bridge’s new eastern tower will make their first recommendations for testing and repairs Thursday, according to Caltrans officials.
Among the recommendations chief bridge engineer Brian Maroney was expected to ask the Toll Bridge Program Oversight Committee to approve is a dehumidification system to dry the rods, according to Caltrans.
About a quarter of the 424 rods in the base of the 525-foot tower were confirmed this year to have been sitting in standing bay water because a contractor failed to adequately grout the steel tubes surrounding them.
The roughly 25-foot-long rods are designed to keep the tower from sliding on its concrete and steel foundation during an earthquake.
The experts were also expected to recommend Thursday that bridge officials purchase special jacks to facilitate cleaning the rods and conduct new testing to determine what long-term effects the exposure to water might have.
They are also working to identify a substance such as grease that can be used to prevent future corrosion.
Pull testing conducted earlier this year found that the vast majority of the rods were still performing as designed, but two did not pass the test and were removed for laboratory examination.
Threading on both rods had been stripped and one of the rods had microfractures discovered using an electron microscope.
How the rods came to be damaged has not been verified, and it remains unclear just what the long-term effects of bay water on the rods will be.
Caltrans officials have said there should be no concern about the bridge functioning as designed, and that the ongoing testing and work on the rods is simply a matter of getting the best possible performance out of the bridge.
The Toll Bridge Program Oversight Committee met Thursday at noon in Oakland.