Simplified approach for prediction of nonlinear response of bored pile embedded in sand

Based on the ‘t-z method’, this paper presents a simplified approach to analyzing the nonlinear response of a single bored pile embedded in sand. The lateral pile-sand interaction of the pile shaft is modeled using the cylindrical cavity expansion theory, and the axial load-settlement behavior of the pile base is analyzed using the spherical cavity expansion theory. The softening model and hyperbolic model are employed to describe the strain-softening and strain-hardening behavior, respectively, of the axial pile-sand interaction observed in elemental tests. The constrained shear-dilatancy response near the pile shaft and the particle-crushing behavior beneath the pile base are subsequently incorporated into the parameters of the present load-transfer models. Using the proposed load-transfer functions, an efficient iterative program is then developed to predict the nonlinear response of a single bored pile embedded in sand. Comparisons of the responses of the bored pile embedded in sand demonstrate that the present calculated results are generally in good agreement with the well-documented observations and the computed results derived from other approaches. A parametric study is also carried out to assess the influence of some key parameters related to the proposed model on the load-displacement response of a single bored pile embedded in sand.