San Francisco Bay Bridge Drivers are Guinea Pigs

Editor comments

Caltrans Management appears to be using Bay Bridge drivers as test subjects for one of the worst bridge designs and executions in recent memory as they continue to deny the seriousness of the problems and refuse expert advise, coming from the Feds, State, and even their own engineers, on how to mitigate the damage already found.

Is there a deliberate cover-up on one of biggest blunders in Caltrans history? Why is there no high level investigation into any aspect of one of the most expensive and controversial engineering projects undertaken in California in recent memory? Why are they rushing to tear down the old bridge? Are they afraid it may withstand the next big quake and the new bridge will fail?  These questions and many more need to answered.

According to the following SFGate  article, there is a history of Caltrans ignoring expert warnings and concerns as the bridge was being built and tested. They appear to categorically refuse to follow any expert advice. Why are the people making the decision to ignore warnings that have proven accurate to date,  still employed and making those decisions?

What are the priorities of our local governments? Where is the alarm and oversight coming from within the ranks of the state and regional transportation authorities appointed by the state? Where are MTC and ABAG? Are they so involved in their own disputes that they have no time to protect the Bay Bridge? Are city governments so intent on growing populations that they have no time to protect the citizens?

Bay Bridge risks, solutions debated as leaks invade foundation

By Jaxon Van Derbeken: sfgate – excerpt

It wasn’t long after workers finished pouring concrete at the bottom of the new eastern Bay Bridge’s tower foundation that the cracks emerged.

Some of the fissures that began to show up in April 2007 were minor, but the two largest were anything but — they were more than 10 feet long and cut through the 20-inch-thick, steel-bar-reinforced concrete layer designed to block corrosive salt water from reaching the foundation frame and tower anchor bolts that provide stability in a major earthquake.

Caltrans made what turned out to be a crucial decision that spring: Rather than demolish the crack-riddled slab and start over, it approved the contractor’s plan to inject the fissures with industrial-grade glue.

Now the concrete repair has failed, and water is flowing into the foundation and filling the sleeves that hold the 25-foot-long rods anchoring the tower. Some of the 400-plus rods have developed rust and micro-cracks, and at least one rod has broken.

Confronted with the stubborn flooding, Caltrans and the three-official panel that oversees the eastern span project recently made another potentially fateful decision: They would study a way to deal with the rods, but not install equipment that could detect and even counter the threat of water-borne corrosion to the foundation itself, overriding the advice of federal highway officials and some of the state’s own engineering consultants.

Caltrans confident

Caltrans and the bridge’s design firm maintain that the foundation’s steel frame is robust enough to do its main job — provide stability in a major earthquake — even if it is beset by corrosion.

“We continue to have complete confidence” that if salt water keeps invading the foundation, the structure can “withstand a 1,500-year seismic event throughout the 150-year bridge design life,” Robert Dameron, an engineer with the design firm joint venture T.Y. Lin International/Moffatt and Nichol, wrote in a September memo to Caltrans officials.

But experts outside Caltrans say there is no way to be sure the foundation can retain its strength, given the unpredictability of saltwater corrosion’s effects inside steel-and-concrete structures.

“You don’t want to shrug it off,” said Jack Tinnea, a 35-year veteran bridge-corrosion consultant who has worked with government agencies and companies on marine projects from Alaska to Mexico. “I have no idea where (the water) is traveling, and neither do they.”

Running late

When the foundation concrete cracks emerged in 2007, Caltrans quickly realized that 22 of them were wider than the agency deemed acceptable.   But the bridge project was already behind schedule, and ordering the foundation rebuilt would have added months to the job.

Instead, Caltrans had the cracks filled with high-strength industrial glue, then lowered the structure into the bay.

By 2014, water started showing up in the sleeves that hold the 25-foot-long anchor rods. At first the source appeared to be rain, but later tests showed it was salt water seeping in through the foundation.

After convening a panel of experts, Caltrans officials downplayed the flooding danger to the foundation, which now sits atop 13 steel-and-concrete piles driven into the bay floor… (more)

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