Based on the Mixture theory and the principles of continuum mechanics, a dynamic three-
phase model for partially saturated poroelasticity is established as well as the corresponding
governing equations in Laplace domain. The three-dimensional fundamental solutions are
deduced following Hörmander's method. Based on the weighted residual method, the
boundary integral equations are established. The boundary element formulation in time
domain for partially saturated media is obtained after regularization by partial integration …