Abstract
Undrained formulation of saturated sand presented in an accompanying paper is used to assess the response of an isolated pile under an applied pile head load moment combination assuming undrained conditions in the sand. The strain wedge model for the drained response (a nonlinear three-dimensional model of a flexible pile in soil) has been extended to assess the undrained response of a laterally loaded pile in sand. The paper characterizes the reduction in pile response due to a drop in sand strength and Young's modulus as a result of developing sand liquefaction. The technique presented yields the undrained p-y curves along the deflected length of the pile showing a distinct difference from the drained soil-pile interaction response. The undrained strain wedge model takes into account the effect of pile properties (such as shape, pile-head condition, and bending stiffness) as well as the properties of the sand on the resulting nonlinear undrained response.