Abstract:According to the failure mode of soil mass observed from tests,the corresponding failure mechanism is proposed to solve the lateral bearing capacity of rigid piles embedded in c-j soil with upper bound analysis method. The three-dimensional failure mechanism that consists of three deformation failure regions and the reasonable velocity field that meets kinematical boundary condition of each deformation failure region are assumed. The mathematical model of the upper bound solution of the lateral bearing capacity for smooth rigid piles is established and solved. It is found that the difference between the upper bound solution and the finite difference solution of the lateral bearing capacity of smooth rigid piles is little. In addition,the upper bound solution of the lateral bearing capacity of rough rigid piles is obtained by modifying that of smooth rigid piles according to the results acquired from finite difference method. The three-dimensional limit analysis provides a simple and effective computing method for the lateral bearing capacity of rigid piles.