On the same day the California Department of Transportation used a live public Webinar to defend its safety testing of the new San Francisco-Oakland Bay Bridge tower foundation, the newspaper that started a safety controversy, The Sacramento Bee, refused Caltrans’ request to retract its most recent story.

Caltrans’ acting director Malcolm Dougherty sent a letter June 7 to Joyce Terhaar, executive editor of the Bee, requesting an immediate retraction of a May 27 story (“Records Raise Doubts on Bay Bridge Concrete”) that asserts a subcontractor disclosed to Caltrans the results of a 2007 foundation test that revealed the concrete hadn’t hardened sufficiently along with other testing problems.

In a statement on June 15, Terhaar said that there is “no reason” for a retraction: “Our information was vetted by internationally known experts and supported by Caltrans’ own documents.”

At issue specifically were testing methods done on two of the 13 pilings that anchor the self-anchored suspension bridge tower section of the new east span. On Pile 3, the subcontractor, Olson Engineering, Denver, did a crosshole sonic logging (CSL) test in 2007 outside of Caltrans’ authority; the test, according to the Bee, conducted four days after the pour found “a large section of concrete that was very poor or not fully set.” Dougherty, in a letter to the Bee, said that the department does not use CSL testing and instead used a gamma-gamma logging (GGL) test that did not find any defects in the concrete and that the concrete hardened correctly after 28 days, the department’s normal testing schedule.

And on Pile 8, The Sacramento Bee claimed that the pile had “inferior concrete” and was “plagued by test and construction problems.” Dougherty countered in his letter that all tests – the “slump test” performed during the pour, the “break test,” the GGL tests performed after the pour and the later chipping – show “no abnormalities.” Dougherty said this information was provided to the Bee reporter, Charles Piller.

Caltrans’ webinar on June 15 covered the same ground and showed videos of its procedures on the concrete pours of the rebar cages of the pilings. Both Tony Anziano, toll bridge program manager, and Dr. Brian Maroney, lead bridge designer and deputy program manager, reiterated that regardless of the procedural criticisms, Caltrans’ foundation construction emphasizes an “abundance of redundancy,” meaning that, for example, the foundation itself did not require 13 pilings but they did it anyway. Also, in the soil analysis, Maroney said that they drilled 7 sample holes around the pilings area to be extra sure about potential ground motion effects.

After the hour-long webinar, Maroney said, “I hope you have a sense of why I’m very confident in the foundation of the SAS tower.

“I hope you understand what we sampled, designed, constructed and inspected. We tested not only the concrete, but the reinforcing steel and the structural steel and that’s fundamentally why I’m confident. Facts are facts.”


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