复合地基荷载传递规律及变形计算

基于文献1]推荐的竖向变形模式及文献2]推荐的径向变形模式,利用弹性理论及桩-土位移协调条件建立了桩及桩周土的控制微分方程,并由此推导出了路堤荷载作用下复合地基加固区桩及桩周土压缩量计算的解析式,同时得出了桩、桩周土中竖向应力及桩侧剪应力计算的解析式。为验证该方法的可行性,通过算例将该方法所得结果与有限元结果进行了对比,同时也与模型试验结果进行了比较。算例及模型试验结果均表明:该方法在分析路堤荷载作用下复合地基的荷载传递规律及加固区的变形时具有足够的精度,且该方法计算工作量小,便于工程应用。

Load transfer law and deformation calculating of the composite foundation

Based on the vertical deformation modell] and the radial deformation model2], the control differential equations of pile and pile-surrounding soil are established by the elastic theory and the pile-soil displacement coordination condition. The analytical formulas calculating deformation of pile and pile-surrounding soil in the reinforcing area of the composite foundation are derived under the embankment load, at the same time,the analytical formulas calculating the pile side shear stress and the vertical stress of pile and pile-surrounding soil are obtained. For verifying feasibility of the proposed method, the results acquired by the proposed method are contrast with the finite element by way of calculating example, and also, carrying on the model experiment. All results indicate: the proposed method has enough precision to analyze load transfer law and deformation of the reinforcing area of the composite foundation under the embankment load, it is simple to calculate, and is easy to engineering application.