SEISMIC EVALUATION OF WHARVES AND EMBANKMENTS AT THE PORT OF OAKLAND, CALIFORNIA

摘要

The Port of Oakland is located in a seismically active region, the San Francisco Bay Area. Wharf structures at the Port are generally at-grade deck structures supported by piles that are embedded in the embankment and in the sub-sea floor soils. Wharves are strongly affected by interaction between the pile/deck structure and the embankment during strong seismic shaking, particularly when weak or liquefiable soils exist in the embankment. Dynamic soil-structure interaction analyses were performed using the computer program FLAC (Fast Lagrangian Analysis of Continua) for several earthquake scenarios. The model was calibrated by comparison with damage experienced at the Port during the 1989 Loma Prieta earthquake. The Port experienced moderate shaking during this earthquake. An acceleration time-history recorded at the Outer Harbor Terminal had a PGA of 0.29g. The FLAC numerical model included the piles, deck, embankment and foundation. Non-linear spring elements were used between the piles and soil to account for p-y and t-z soil-structure interaction effects.