Nonlinear response of laterally loaded piles and pile groups

Abstract

In spite of extensive studies on laterally loaded piles carried out over years, none of them offers an expedite approach as to gaining nonlinear response and its associated depth of mobilisation of limiting force along each pile in a group. To serve such a need, elastic-plastic solutions for free-head, laterally loaded piles were developed recently by the author. They allow the response to be readily computed from elastic state right up to failure, by assigning a series of slip depths, and a limiting force profile (LFP). In this paper, equivalent solutions for fixed-head single piles were developed. They are subsequently extended to cater for response of pile groups by incorporating p-multipliers. The newly established solutions were substantiated by existing numerical solutions for piles and pile groups. They offer satisfactory prediction of nonlinear response of all the 6 single piles and 24 pile groups investigated so far after properly considering the impact of semi-fixed head restraints. They also offer the extent to ultimate state of pile groups via the evaluated slip depths. The study allows ad hoc guidelines to be established for determining input parameters for the solutions. The solutions are tailored for routine prediction of nonlinear interaction of laterally loaded fixed-head piles and capped pile groups.