A time-domain FEM approach based on implicit Green’s functions for the dynamic analysis of porous media

This paper describes an original time-domain formulation to analyse saturated porous media. Standard finite element procedures are employed to numerically discretize the spatial domain of the model and a time-marching scheme based on the mechanical Green’s function of the problem is considered. The Green’s function matrices are implicitly and numerically evaluated, taking into account the Newmark method. The present methodology allows the system of equations of the solid and fluid phase to be treated separately, providing a more efficient and accurate solution procedure (smaller, simpler and better conditioned systems of equations are analysed). At the end of the paper, numerical examples are presented, illustrating the potentialities of the new approach.