Effect of Slope Angle on Pile Response

Objectives: The present paper aims at finding the influence of soil slope on reduction of horizontal (lateral) load carrying capacity of pile embedded at the crest of clay slope. Analysis: 3D finite element analysis has been carried out using PLAXIS 3D. In each analysis, initial stresses developed due to gravity loading are calculated in the first step. In the second step, pile construction is simulated by interchanging the material properties of the appropriate volume elements. Finally, lateral load corresponding to the prescribed horizontal deflection of 0.1D at pile top is calculated in last step. Findings: The effect of various factors such as slope angle, Length to Diameter ratio of pile and undrained cohesion of soil on horizontal load carrying capacity of pile has been studied. From the study, it is perceived that the load carrying capacity for a prescribed displacement increases with increase in length to diameter ratio and undrained cohesion whereas capacity reduces with increase in slope angle. There is approximately 10% and 27% decrease in the load carrying capacity when the slope angle changes from 0o to 30o and 0o to 55o respectively. For pile having L/D = 10, the deflections are observed throughout the length of the pile where as for pile having L/D = 25, the deflections are extending up to certain depth and after that depth, the deflection is zero. Applications/Improvement: Effect of sloping ground condition on pile response is quantified by numerical analysis. Reduction in the ultimate capacity for sloping ground condition is presented for range of parameters.It is possible to predict the pile response for sloping ground condition for a given pile response in horizontal ground and predicted reduction from tables.