Pile end-bearing capacity of sand related to soil compressibility

A simple method based on theoretical and experimental considerations is presented to predict the pile end bearing capacity and load-settlement curve in sands in relation to soil compressibility. The key to the method is in the assumption of a failure mode with a spherical cavity expansion pressure given as a function of the soil compressibility, shear stiffness and friction angle. The practical prediction of pile end-bearing capacity in sandy ground is discussed in terms of a compressibility factor, friction angle and shear stiffness. Further, the pile tip settlement behaviour is also discussed based on an empirical model incorporating the pile end bearing capacity from a cavity expansion analysis with a Kondner type hyperbolic function. The applicability of the proposed method is verified by comparing the predicted results with the results from a series of model pile load tests and a database for in-situ pile load tests in sands.