水平受荷斜桩双曲线型p-y曲线的构建及其应用

基于模型试验获得中密干砂中水平受荷斜桩的桩侧土反力p与桩身位移y的关系曲线，探讨斜桩和直桩的桩侧极限土反力、初始地基反力模量与桩身倾角的关系，构建砂土地基斜桩的双曲线型p-y曲线. 应用建立的双曲线型p-y曲线对文献16,20]的模型试验进行计算，计算结果与实测结果具有较好的一致性，验证了建立的双曲线型p-y曲线的合理性. 运用建立的p-y曲线，分析影响水平受荷斜桩性状的因素，结果如下. 1）与桩顶自由条件相比，斜桩桩顶固支可以有效地减小桩顶横向位移、桩身最大弯矩及最大剪力. 2）在竖向下压荷载作用下，正斜桩和直桩的桩顶横向位移、桩身最大弯矩及最大剪力随着竖向下压荷载的增加而增大，负斜桩的桩顶横向位移、桩身最大弯矩及最大剪力随着竖向下压荷载的增加先减小至0，再反向增大. 在竖向上拔荷载作用下，直桩的桩顶横向位移、桩身最大弯矩及最大剪力随着上拔荷载的增加而减小，正斜桩的桩顶横向位移、桩身最大弯矩及最大剪力随着上拔荷载的增加先减小至0，再反向增大，负斜桩的桩顶横向位移、桩身最大弯矩及最大剪力随着上拔荷载的增加而增大.

Formation and application of hyperbolic p-y curves for horizontally loaded single batter piles

Relation curves of lateral resistance force per unit length to pile deflection were measured for single battered piles based on model tests under horizontally loads in medium-dense dry sand. The relations of the profile of limiting lateral resistance force per unit length (LFP) and initial subgrade reaction coefficient to batter angle of inclined piles and plumb piles were analyzed. A hyperbolic expression was used to establish a p-y curve approach for battered pile subject to lateral loads. The results were calculated by using the hyperbolic p-y curves established herein and that reported in literatures. The calculation results accorded well with the experimental results, which verified the rationality of the above method. The approach was used to analyze the behaviors of laterally loaded batter piles. 1) The pile-top lateral displacement, the maximum bending moment and the maximum shearing force in a fixed-head batter pile are less than that of a free-head batter pile with which induced the same load. 2) The vertical downwards load on the pile top can increase the pile-top lateral displacement, the maximum bending moment and the maximum shearing force for both the positively battered piles and the plumbed piles. The pile-top lateral displacement, the maximum bending moment and the maximum shearing force will firstly decrease to zero and then increase reversely with the increase of vertical downwards load in the case of negatively battered piles. The pile-top lateral displacement, the maximum bending moment and the maximum shearing force of the plumbed pile, under a same lateral load, will decrease with the increase of the vertical uplifting load, while that of the positively battered pile decreases to zero and then increases reversely with the increases of the vertical uplifting load, and that of the negatively battered pile increases with the increase of the vertical uplifting load.