Axial Response of Tapered Piles in Cohesive Frictional Ground

This paper presents a theoretical model for the analysis of the axial response of tapered piles in cohesive frictional ground. The operating characteristics of tapered cylindrical piles are identified on the basis of experimental observations. In contrast to cylindrical piles, the side resistance of tapered piles continues to increase with the axial deformation because of the additional radial expansion of the ground caused by the tapered pile wall. A simplified theoretical model applicable to piles with small taper angles is developed for the analysis of the response of these piles. The application of the model to a field pile test indicates that it is very effective in predicting the side resistance development of tapered piles. A limited parametric study indicates that in many practical situations tapered piles offer a design option that is more economical than conventional uniform cross-section piles.