Dynamic p-y curves for vertical and batter pile groups in liquefied sand

In this study, centrifuge model tests of vertical and batter pile groups in liquefied sand were conducted on a centrifuge shaking table. The dynamic p-y curves for these pile groups before and during sand liquefaction were obtained from calculations based on test data. The results confirm that liquefaction contributes to a reduction in the energy consumption of pile foundations, with the degradation effect being more pronounced for batter pile groups. At shallow depths, the difference in the backbone gradients of the p-y curves after liquefaction for vertical and batter pile groups indicates that the lateral stiffness of a batter pile group is greater than that of a vertical pile group. As shaking intensity increases, the lateral stiffness of a vertical pile group increases with depth during the late stage of sand liquefaction. However, the lateral stiffness of a batter pile group during liquefaction does not vary with depth. The results of this study provide a reference for the seismic design of vertical and batter pile groups in liquefied soil.