A Method for Predicting the Effect of Piles on Slope Behaviour

摘要

This paper describes a finite element technique for analyzing the undrained behavior of clay slopes reinforced by piles. This technique allows consideration of the effects of failure within the soil or the pile, and flow of soil past the piles. The deformation and stability of the soil can thus be analyzed for various pile arrangements and values of pile stiffness, without the need for making arbitrary assumptions regarding the deformed shape of the pile or the location of the failure surface within the soil. A parametric study of the effect of piles on the performance of a particular slope geometry is reported. It is shown that the slope performance depends largely on the pile arrangement, pile stiffness, the head and tip restraint conditions of the piles, and the details of the soil profile. The most effective results are obtained when restraint is provided at the head and tip of the pile and when the piles are relatively stiff. The effect of piles on slope deformation and stability increases very slowly with increasing pile stiffness, so that piles of normal stiffness without tip or head restraint, have only a small effect on slope stability.