The documents, contained in 20 binders, include inspection reports, photographs, contractor invoices and newspaper clippings. They were released Tuesday in response to a public records request filed by news organizations.
On Sept. 5, as Caltrans was putting into a place a temporary detour on the Bay Bridge's east span, inspectors discovered a crack in one of the bridge's structural support beams. According to an inspection report dated the next day, "The fracture measured 3/4" wide at the pin hole to 1 11/16" wide at the outer edge and is 12" in length."
Caltrans engineers designed an emergency fix for the crack and worked round the clock to install it.
"The concept and basic dimensions shown in the draft are good," wrote Caltrans' lead bridge engineer Brian Maroney in an e-mail dated Sept. 7.
However, less than two months later on Oct. 27, the repair failed, and a 5,000-pound piece of metal came crashing down on to the deck of the bridge during the evening commute.
At least one inspector saw problems with the way the repair was being assembled.
"The welds observed by the (Quality Assurance) inspector were found to have inadequate fill and excessive undercut at several locations," according to a report dated Sept. 7. "The areas of unacceptable weld was marked for repair and immediately repaired by the welder on site."
In a document dated Oct. 30, Caltrans engineers wrote that they were only able to visually inspect about 75 percent of the repair mechanism's welds prior to installation.