A p–y curve model for laterally loaded XCC pile in soft clay

Abstract

This paper presents a p–y curve model for laterally loaded X-sectional cast-in-place concrete (XCC) piles, which are a type of non-circular cross-sectional pile, in soft clay. The recently developed empirical solutions for the elastic stiffness and the ultimate lateral resistance of the two-dimensional laterally loaded X-shaped cross-sectional pile segment–soil system by the authors using the complex variable elasticity theory and finite element limit analysis are used as the two key parameters in constructing the p–y curve. An elastic–perfectly plastic p–y curve is immediately obtained with the linear elastic state described by the elastic stiffness of the two-dimensional system, and the perfectly plastic state is controlled by the ultimate lateral resistance. Furthermore, to consider the nonlinear behaviour, a more robust model using the hyperbolic function is selected for producing the p–y curve with the elastic stiffness and the ultimate lateral resistance incorporated. Subsequently, the p–y model is introduced to the Winkler model to generate solutions for the response of laterally loaded XCC piles. The proposed model considers the non-circular cross-sectional effect of the XCC pile and can also be regarded as a simple method for constructing the p–y curve for other non-circular cross-sectional piles.