Soil Motion Computations by Characteristics Method

In this study the characteristics method is applied to wave propagation corresponding to earthquake intensities in models of unsaturated and saturated soils. Shear waves developed in linear, or in strain-softening materials, and pressure waves in viscoelastic materials are considered. One-dimensional transmissions in unsaturated layered systems are treated first, then the method is applied to two-dimensional simulations by the lattice work approach. The latter method may also be extended to treat three-dimensional problems. Pore pressure transients are investigated in a one-dimensional approach based on Darcy's law. By prescribing reductions of void ratios as a function of time, zones of potential liquefaction may be identified and their movement traced. By use of a lattice work representation, transient pore pressure within the upstream portion of an earth dam are investigated.