扩底桩桩侧土水平抗力的分布特性

桩侧土的水平抗力是计算桩基水平承载力的重要因素。本文对扩底桩基础桩侧水平抗力特性进行研究。制定模型试验方案,进行扩底桩水平加载室内模型试验。整理模型试验加载数据获得扩底桩在水平荷载作用下的桩顶加载位移曲线、桩侧土抗力、桩底土抗力的分布曲线等重要数据,分析各数据获得扩底桩桩侧土水平抗力的分布规律。通过有限元软件模拟不同桩长、扩底尺寸的扩底桩承受水平荷载时的加载情况,通过对数值模拟结果的分析获得扩底桩受水平荷载作用时的受力变形特性,研究不同尺寸参数对扩底桩水平受力特性的影响情况。研究表明,桩长越短越有利于发挥扩大头的嵌固作用。根据对桩底扩大头处土抗力分布曲线的分析研究扩大头的嵌固力作用,进而提出扩大头嵌固力的计算方法。

Distribution characteristics of horizontal resistance of soil on the side of belled pile

The horizontal resistance of the pile side soil is an important factor in calculating the horizontal bearing capacity of the pile foundation.In this paper,the horizontal resistance characteristics of the pile side of the belled pile are studied.A model test plan is developed and the indoor model test of the horizontal load of the belled pile is carried out.The model test loading data was used to obtain the important data such as the pile top loading displacement curve,the pile side soil resistance force and the pile bottom soil resistance distribution curve under the horizontal load.The distribution of horizontal resistance of the lateral soil piles was obtained by analyzing the measured data.The finite element software is used to simulate the loading condition of the piles with different pile lengths and bottom-expanding dimensions under the horizontal load.The numerical simulation results are analyzed to obtain the force deformation characteristics of the belled piles subjected to horizontal loads,and different dimensional parameters are studied.Research shows that the shorter the pile length,the greater the embedding effect of enlarged head.According to the analysis of the soil resistance distribution curve at the enlarged end of the pile bottom,the effect of the embedded fore of the head is enlarged,and then the calculation method of expanding the head inserting fore is proposed.