An analytical p-y curve method based on compressive soil pressure model in sand soil

Abstract

With the high-quality development of urban buildings, higher requirements are come up with for lateral bearing capacity of laterally loaded piles. Consequently, a more accurate analysis to predict the lateral response of the pile within an allowable displacement is an important issue. However, the current p-y curve methods cannot fully take into account the pile-soil interaction, which will lead to a large calculation difference. In this paper, a new analytical p-y curve is established and a finite difference method for determining the lateral response of pile is proposed, which can consider the separation effect of pile-soil interface and the coefficient of circumferential friction resistance. In particular, an analytical expression is developed to determine the compressive soil pressure by dividing the compressive soil pressure into two parts: initial compressive soil pressure and increment of compressive soil pressure. In addition, the relationship between compressive soil pressure and horizontal displacement of the pile is established based on the reasonable assumption. The correctness of the proposed method is verified through four examples. Based on the verified method, a parametric analysis is also conducted to investigate the influences of factors on lateral response of the pile, including internal friction angle, pile length and elastic modulus of pile.

摘要

随着城市建筑的高质量发展，对桩基的水平承载能力提出了更高的要求。因此，更准确地预测 水平受荷桩在允许位移范围内的横向响应是重要的。然而，现有p-y 曲线法不能充分考虑桩土相互作 用，导致预测的桩基水平响应差异较大。本文提出了一种新的理论p-y 曲线法，该方法可以考虑桩土 界面脱开效应和环向摩擦系数。在此基础上，根据有限差分模型建立了桩身横向响应分析方法。将径 向土压力视为初始径向土压力和径向土压力增量两部分，得到了径向土压力的解析表达式。另外，还 建立了桩侧径向土压力与桩身水平位移的关系。通过4 个算例验证了所提方法的正确性。在此基础上， 对内摩擦角、桩长和桩的弹性模量等的变化引起的桩身横向响应进行了参数分析。