Access Tunnel at Transfer Platform Facility BART
East Contra Costa County, CA

Access Tunnel at Transfer Platform Facility
Bay Area Rapid Transit District
East Contra Costa County, CA

We provided the final PS&E for a buried 110-foot-long single-cell concrete box structure (tunnel) and 150-foot-long U-shaped retaining wall. The new tunnel, via a new opening, ties into the existing tunnel (located east of the Pittsburg/Bay Point Station) under 10 feet of fill, travels eastward and ties into the new U-shaped wall which comes up to grade to provide access to the new Transfer Platform Facility. The analysis involved 3-D modeling of the entire new tunnel. The design of
the new tunnel and U-wall involved structural modifications to the existing tunnel and the requirement to maintain traffic along SR4 during construction.