The negative friction problem of single pile

which is in layered porous half-space under the surface load

is studied by using Biot’s consolidation theory and integral equation method. The poroelastic half-space considered rheology is governed by Biot’s consolidation theory and the Merchant model is used to describe the porous half-space’s rheology. The second kind of Fredholm integral equations of the pile subjected to circular load in layered porous half-space is obtained by using the fundamental solution. The integral equations can be simplified by means of Laplace transform methods .These equations can be transferred to each layer by the transfer matrix and stiffness-matrix approach. By the numerical solutions of the integral equations and the corresponding inverse integral transforms the displacement

axial force

pore pressure and shear stress of the pile and pore pressure along the pile axis are obtained. It is indicated that the shear stress of the pile and pore pressure along the pile axis are obviously layer built.