Dynamic analysis of an elastic plate on a fissured poroelastic half-plane under a moving load

Abstract

This paper studies the dynamic response of an elastic concrete plate on a fissured poroelastic rock medium to a moving load under plane strain conditions. The plate is assumed to be thin, isotropic, and linear elastic. The fissured poroelastic rock medium is isotropic, fully saturated with water, and characterized by two types of porosity, one due to fissures separating it into blocks and one due to the pores in those blocks. The load is assumed to be uniformly distributed over a finite length and moves with constant speed. The problem, which describes a case of rigid pavement, is solved analytically/numerically by the complex Fourier series method. Thus, the load and the plate and rock medium displacements are expanded in complex Fourier series with respect to the horizontal coordinate (motion direction) and the time. Upon substitution of these expansions into the equations of motion for the plate and the half-plane rock medium, the corresponding partial differential equations are reduced to algebraic and ordinary differential equations, respectively, which can be easily solved. The resulting response solution is verified by comparison with existing solutions for special cases. Parametric studies are finally conducted for assessing the effects of problem parameters like porosities, permeabilities, thickness of the elastic plate, and vehicle load speed on the response of the plate.