San Francisco-Oakland
Bay Bridge East Span
San Francisco/Oakland, California

SOHA Engineers is part of a team that provides services in the analysis and design of the superstructure of the causeway, analysis and design of the tower for the signature span, nonlinear static and dynamic analysis and design of seismic protective systems. The new bridge for the San Francisco-Oakland Bay Bridge East Span replacement is a 2.1-mile-long structure consisting of a Signature Span and a Causeway connecting the tunnel at Yerba Buena Island to Oakland. The Signature Span consists of a single tower, self anchored, asymmetric suspension bridge, with a main span of approximately 370 meters. The Causeway has typical spans of 160 meters with variable depth concrete deck or constant depth steel deck. The new bridge will have 2 five-lane roadways placed side-by-side with 10-foot shoulders. A 15-foot bike lane will be provided on the south side. The bridge is expected to be commissioned in 2003.

Sacramento River Bridge
Rio Vista, California

Seismic evaluation and rehabilitation of the Sacramento River Bridge. Originally built in 1944, this bridge carries two lanes of traffic 2,500 feet across the Sacramento River. It is a steel truss structure with a vertical lift span. In 1960, the bridge received the Most Beautiful Steel Bridge award from the American Institute of Steel Construction. Seismic evaluation included linear response spectrum, nonlinear static pushover and nonlinear dynamic time-history analyses. Energy dissipation devices are used for the seismic rehabilitation of the bridge including lead core rubber isolation bearings and lead extrusion dampers.

Richardson Bay Bridge
Marin County, California

Seismic retrofit of the Richardson Bay Bridge and Overhead which is 2,864 feet long and carries ten vehicular lanes of traffic over the navigable Bay. The bridge consists of 44 spans, reinforced concrete box girders, and precast “I” girders. The seismic retrofit scheme took into consideration the extraordinary environmental sensitivity of the Bay, especially during the construction phase.

Alameda Creek Bridge
Alameda County, California

Structural engineering services for this bridge which consists of a CIP prestressed box girder superstructure on single column bents, supported by spread foundations. With an overall length of 885 feet, it replaces the existing two-lane structure, Route 84, and connects City of Fremont with the town of Sunol. The replacement structure crosses over Union Pacific railroad tracks and the Alameda Creek, with a longest span of 150 feet.

Airport Railway Transit Guideway
San Francisco International Airport

Structural design of the west side of the Airport Railway Transit Guideway (ART), which is a portion of the San Francisco International Airport Master Plan. It contains single- and double-deck aerial structures carrying ART and BART trains, and it includes three stations. One of the most challenging parts of this segment is a 1,000-foot-long double-deck portion. This nine-bent structure carries BART trains on its lower level and ART cars on the top. The structures are designed to meet a combination of the BART and the ART seismic design criteria and will be constructed on bay mud soil conditions.

Los Angeles County Bridges
Los Angeles County, California

This was an on-call multi-discipline, multi-task engineering services agreement for the seismic retrofit of County-owned bridges. Projects included the Mulholland Bridge and Queensway Ramps J & K. SOHA’s scope of work included seismic evaluations, retrofits studies, and PS&E packages.

5th and 6th Street Viaduct
Alameda County, California

Seismic retrofit of this viaduct which consists of six structures built between the years 1953 and 1984. It has a total length of 2,820 feet and varies in width from 125 to 227 feet. The viaduct carries Route 880 traffic over local streets north to the new Cypress structure and the Route 980 connectors and south to the City of San Leandro.