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Seismic retrofit of existing 4.5-mile-long bridge with two spans across active shipping channels. The contract consisted of major renovations and seismic retrofitting of both the superstructure and foundation. The Richmond-San Rafael Bridge is one of the largest and most complicated bridges in the state. Factors such as variable soils and foundations, aged and complex structures, heavy traffic volume, utilities, shipping concerns and environmental issues combined to make this project extremely challenging.

Originally completed in 1956, the Richmond-San Rafael is the longest steel bridge in the San Francisco Bay Area. The four-year rehab project was the most complex single retrofit program ever attempted by Caltrans. Among the many tasks were strengthening the piers and installing "viscous dampers" — essentially, massive shock absorbers. Despite the many challenges, the project came in $136 million under budget. While most of the bridge structure was retrofitted, the low-lying trestle section on the Marin County side had to be completely replaced. Caltrans and the contractors replaced the entire trestle, section by section, while keeping the bridge open to traffic the entire time.

To make matters even more challenging, the structural maintenance of the bridge deck — originally scheduled to take place after the completion of the retrofit — was moved up and performed concurrently with the retrofit. All of the expansion joints were replaced, and the concrete deck sections were repaired.