ABSTRACT
Positive excess pore water pressures may develop in saturated fine sands during the strong motion phase of the earthquake, inducing a reduction of the state of effective stress, and hence of the strength and of the stiffness of the soil, which, in extreme cases, may lead to liquefaction. A reliable numerical prediction of seismically induced excess pore water pressures requires the development of a dynamic fully-coupled formulation capable of reproducing solid-fluid interaction together with the adoption of advanced constitutive models. In this work, the propagation of shear waves in layered and homogeneous saturated sand is examined numerically. The paper describes an original fully coupled dynamic u-p formulation, which was implemented in the finite element code FEAP 8.4 (Taylor 2013) together with the advanced constitutive model SANISAND (Dafalias and Manzari 2004), which was adopted to describe the response of the solid skeleton. The field equations are formulated in a fully saturated condition.
