Wave-Induced Dynamic Response and Liquefaction of Transversely Isotropic Seabed

Abstract

The problem of dynamic response and momentary liquefaction of a transversely isotropic seabed subjected to water waves was treated analytically using a fully coupled dynamic model. The dynamic governing equations were first formulated as a set of sixth-order ordinary differential equations in terms of displacements of solid skeleton and excess pore pressure whose general solutions can be readily derived. Based on the appropriate boundary conditions, explicit solutions for soil displacements, effective stresses, and excess pore pressure as well as momentary liquefaction potential were subsequently determined in closed forms for the cases of water waves propagating over a transversely isotropic poroelastic seabed. The validity and accuracy of the proposed formulations and solutions were further verified through comparisons with existing analytical solutions that were special cases of the more general ones currently addressed. Some selected charts are presented and the effects of soil anisotropy on the calculated effective stresses and excess pore pressure as well as on the momentary liquefaction depth of a transversely isotropic saturated seabed are investigated and discussed.