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Engineering Geology of the BART System (2000)
ay Area Rapid Transit District date back to 1947, when the joint Army-Navy board suggested construction of a rapid transit tube beneath San Francisco Bay, to speed travel between Oakland and San Francisco. During the Second World War (1939-45), railroad, aviation, logistical supply and port facilities mushroomed around the Oakland-Alameda estuary, surpassing San Francisco in volume of commerce.
Believing that just enough steel was needed to handle the ring stresses because the soil loads arch around the flexible lining, University of Illinois Professor Ralph Peck found himself in the influential position of being one of the external consultants hired by Parsons-Brinkerhoff to review the overall plans and provide advice to the design team, between 1964-73. Kuesel (1968) succeeded in convincing others on the design team thin wall circular steel linings should work well in the soft clay soils that dominated the transbay tube alignment, due to its flexibility (to withstand differential settlement) and high tensile strength (200 psi) at the segment connections, which would offer greater performance redundancy in event of an earthquake. Figuers, S., 1998, Groundwater Study and Water Supply History of the East Bay Plain, Alameda and Contra Costa counties, CA: Norfleet Consultants report to The Friends of the San Francisco Estuary, June, 90 p. Gerwick, Ben C., Jr., 1965, Excavation is shored in a new way: Western Construction News, v. 43:8 (August), p. 47.
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