Shear hysteretic elasto-plastic earthquake response of soil systems

An analytical/numerical procedure is developed to calculate the shear hysteretic elasto-plastic earthquake response of soil systems. Dynamic level ground response as well as earth-dam response is evaluated on the basis of the analytical one-dimensional (ID) shear-beam and shear-wedge models respectively. Soil is modelled as an elasto-plastic hysteretic material following the principles of flow or incremental plasticity. Stiffness and strength degradation of this material may be specified as a function of accumulated plastic strain and associated pore-pressure build-up. The entire numerical procedure may be executed on a personal computer and consequently qualifies as a versatile tool in conducting preliminary design calculations or parametric-type investigations. Using this procedure, the responses of the Mexico City SCT site during the September 19, 1985 earthquake, and the California Wildlife site during the November 24, 1987 earthquake are computed and compared to those actually observed.