Analytical Solution for the Transient Response of Cylindrical Cavity in Unsaturated Porous Medium

Abstract

The transient response of a pressurized long cylindrical cavity in an infinite unsaturated porous medium is considered for the first time. Solutions are presented for three different prescribed transient radial pressure types, namely step load, gradually applied step load, and triangular pulse load, acting on the surface of a permeable as well as an impermeable cavity surface. Time domain solutions are obtained by inverting Laplace domain solutions using a reliable numerical scheme. The validity of the solution is confirmed by comparing with the one in which the infinite medium is assumed as a saturated porous medium. The time histories of radial displacements, hoop stresses and pore fluid pressures corresponding to a cavity in a representative unsaturated porous material are presented. A detailed parametric study is described to illustrate the saturation influence on the responses of the radial displacements, hoop stresses, and pore fluid pressures at the cavity surface.