Transient wave propagation in a one-dimensional poroelastic column

Blot's theory of porous media governs the wave propagation in a porous, ela stic solid infiltrated with fluid. In this theory, a second compressional w ave, known as the slow wave, has been identified. In this paper, Blot's the ory is applied to a one-dimensional continuum. Despite the simplicity of th e geometry, an exact solution of the full model, and a detailed analysis of the phenomenon, so far have not been achieved. In the present approach, an analytical solution in the Laplace transform domain is obtained showing cl early two compressional waves. For the special case of an inviscid fluid, a closed form exact solution in time domain is obtained using an analytical inverse Laplace transform. For the general case of a viscous fluid, solutio n in time domain is evaluated using the Convolution Quadrature Method of Lu bich. Of all the inverse methods previously investigated, it seems that onl y the method of Lubich is efficient and stable enough to handle the highly transient cases such as impact and step loadings. Using properties of three widely different real materials, the wave propagating behavior, in terms o f stress, pore pressure, displacement, and flux, are examined. Of most inte rest is the identification of second compressional wave and its sensitivity of material parameters.