TIME-DOMAIN EXPLICIT FINITE-ELEMENT METHOD FOR DYNAMIC ANALYSIS OF TRANSVERSELY ISOTROPIC FLUID-SATURATED POROUS MEDIA

We present a time-domain, explicit, finite-element method (FEM) for dynamic analysis of transversely isotropic fluid-saturated porous media (TIFSPM). Wave propagation equations in TIFSPM are derived based on continuum mechanics. An explicit FE procedure for solving wave propagation equations is developed by applying the decoupling technique in the spatial domain and central difference method and the Newmark constant average acceleration method in the time domain. The explicit FEM is applied to simulate dynamic response of TIFSPM, and simulation results are compared with dynamic response of isotropic fluid-saturated porous media (IFSPM). Parametric studies are performed on the anisotropy coefficient to investigate the effect of material anisotropy on TIFSPM dynamic response. We find that dynamic response of TIFSPM is significantly different from that of IFSPM, and anisotropy impacts largely on TIFSPM dynamic response.