奥克兰海湾大桥东跨地震复原工程.ppt

nhbjkbkj Bay Area Toll AuthoritySan Francisco-Oakland Bay Bridge East Span Seismic Replacement Project Self Anchored Suspension Span (SAS) A long history…. On the right track…. ZPMC - Shanghai, China Skyway (2007) Oakland Touchdown Under Construction Completed Skyway Completed Skyway The Self Anchored Suspension Span is the signature segment of the bridge. The single tower design was selected in part due to the better geological conditions just off Yerba Buena Island. The new span will be founded on bedrock and not the redwood tree piles currently stuck in the mud. 19 years ago, on October 17, 1989, a 6.9 magnitude earthquake struck the Bay Area Centered 60 miles away from San Francisco, the Loma Prieta Earthquake collapsed a 50-foot section of the San Francisco – Oakland Bay Bridge, causing two cars to fall to the deck below, leading to the single fatality on the bridge. The bridge was closed for repairs for a month and one day, reopening on November 18. After the bridge was repaired, it was determined that the long term solution for the east span of the Bay Bridge should be replacement. A Signature Self-Anchored Suspension Span was selected to be constructed. The single tower is anchored into bed rock just off the island. The tower is actually composed of four separate legs that are connected by seismic fuses at the top of the tower that are designed to sustain and absorb damage from a major quake. The bridge is has a design life of 150 years. The new bridge design already has a long history that spanned a number of design alternatives and multiple gubernatorial administrations. There have been great challenges from spiking material costs, lack of insurance after 9/11, and only receiving a single bid in 2005. We have turned the corner. After the last round financial challenges, the State legislature passed AB144 that provided a funding package for the project and established the Toll Bridge Program Oversight Committee. The committee is c