Turnback Project Moves Ahead

by David A. Sutter, Senior Project Manager; San Francisco Public Transportation Commission, San Francisco, CA,
James P. Connolly, Construction Manager; Bechtel Civil Co., San Francisco, CA,
Ching Wu, Engineering Manager; Bechtel Civil Co., San Francisco, CA,

Serial Information: Civil Engineering—ASCE, 1996, Vol. 66, Issue 1, Pg. 36-39

Document Type: Feature article


The $202 million Muni Metro Turnback (MMT) Project, scheduled for completion in September 1996, includes an 840 ft section consisting of twin steel-lined tunnels that connects to the Embarcadero Station, runs under Market Street and turns south to the Embarcadero, a 1,120 ft cut-and-cover box structure, where the train turnback and storage facility will be located, a 370 ft U-wall structure that gradually ascends to the surface. the tunnels go through a mixed face condition of fill at top and Bay Mud at bottom, and a significant number of buried timber piles. This article presents the selection of tunneling equipment, excavation methods, excavation support and chemical grouting; specification of timber pile cutting methods; and steel lining analysis and design; and construction of the tunnel and the cut-and-cover sections.

Subject Headings: Tunnels | Steel piles | Construction methods | Wood structures | Wood piles | Wood and wood products | Storage facilities

Services: Buy this book/Buy this article


Return to search