A numerical model for the dynamic response of anisotropic and inhomogeneous seabed under wave action is developed based on the element-free Galerkin method for Biot's dynamic consolidation equations.Variations of the permeability and the elasticity of the soil in the vertical direction,which is an intrinsic feature of the stratified seabed,are considered.The numerical model is validated under isotropic and homogeneous conditions.The effects of the cross-anisotropy and inhomogeneity on the seabed response and shear failure are found to be remarkable.If the vertical increase of elastic modulus is taken into account,a significant decrease of the depth of shear failure can be expected.
This study presents an effective numerical model for the dynamic response of poroelastic seabed under wave action with enhanced performance.The spatial discretization is based on the Element-Free Galerkin(EFG) method and the time integration based on the GN11 scheme.A stability strategy that adopts a smaller number of nodes for the pore water pressure compared with those for the displacements of the soil skeleton is suggested to resolve the similar difficulty as encountered in the finite element method for a problem with mixed formulation when the pore water is incompressible and the soil skeleton impervious.The accuracy of the numerical model is verified through applying it to a typical case with critical permeability.Good agreement between computational and analytical solutions is obtained.
