一种大直径扩底桩的沉降计算实用方法

Practical method for settlement calculation of large-diameter belled piles

根据大直径扩底桩桩端应力的分布特征,利用Mindlin基本解推导了扩底桩桩端沉降计算公式,并给出了沉降影响系数。公式中桩端持力层土体的变形模量用深层平板静力载荷试验测定,但深层载荷试验有时难以实现。为此根据收集的扩底桩工程实测沉降和原型扩底桩静载试验结果,建立了工程中常用的压缩模量与变形模量间的关系,并给出了两者的换算关系。大量的工程实测表明,得出的扩底桩沉降计算公式是实用的。

Based on the stress distribution characteristics of pile tip, a practical method is derived to calculate tip settlement of large-diameter belled piles using the Mindlin fundamental solution. And the settlement coefficient is also given. The deformation modulus of pile tip bearing stratum is determined by deep plate loading test. However, the deep plate loading test is difficult at a certain condition. So, according to a large number of measured settlement data and load test results of large-diameter belled piles, the relationship between the compression modulus and the deformation modulus is obtained. Large numbers of engineering cases indicate that the proposed settlement formula is feasible.