Seismic Design Criteria for Soil Liquefaction.

Abstract

Abstract : The Navy has numerous bases located in seismically active regions throughout the world. Safe and effective structural design of waterfront facilities requires calculating the expected site specific ground motion and determining the response of these complex structures to the induced loading. The Navy's problem is further complicated by the presence of soft saturated marginal soils which can significantly amplify the levels of seismic shaking and liquefy as evidenced in the 1939 Loma Prieta earthquake. Liquefaction is a major factor at the waterfront and most of the damage the Navy has sustained from earthquakes can be attributed to it. The presence of unconsolidated loose cohesionless soils and the high water table makes waterfront sites especially vulnerable. This report establishes liquefaction criteria suited for the design of new facilities and upgrade of existing facilities. The criteria developed herein presents reasonable performance standards balancing performance and damage minimization against the cost of implementation.