An explicit finite element method for dynamic analysis in fluid saturated porous medium-elastic single-phase medium-ideal fluid medium coupled systems and its application

In this paper, an explicit finite element method to analyze the dynamic responses of three-media coupled systems with any terrain is developed on the basis of the numerical simulation of the continuous conditions on the boundaries among fluid saturated porous medium, elastic single-phase medium and ideal fluid medium. This method is a very effective method with the characteristic of high calculating speed and small memory needed because the formulae for this explicit finite element method have the characteristic of decoupling and does not need to solve the system of linear equations. The method is applied to analyze the seismic responses in a reservoir with the consideration of the dynamic interactions among water, dam, sediment and foundation rock. The vertical displacement at the top point of dams is calculated and some conclusions are given.