Novel Analytical Methods for Predicting the Response of Bored Piles in Sand

In this work easy-to-use tools are presented for the prediction of the load-settlement response of the bored piles in sandy soils. At first, an analytical solution, based on the well-known similarities between the pile tip behaviour and that of an expanding spherical cavity in an elasto-plastic medium, is proposed. In particular, this approach has been employed adopting the Yu & Houlsby (1992) solution for the cavity expansion problem. Then an effective framework for the evaluation of the shaft load-settlement response for bored piles embedded in sandy soils is presented. For the evaluation of the shaft response, a physically based analytical model is proposed to compute the ultimate shaft friction, based on that proposed by Mascarucci et al. (2016), taking into account the horizontal stress increase during the loading process produced by the dilatancy occurring in the shear band. The proposed methods require standard input parameters, given the ordinary in situ and laboratory tests employed in the current practice. Thus, adopting both proposed solutions, it is possible to obtain a complete framework for the evaluation of the single pile load-settlement response.