层状地基中桩基础的竖向荷载位移关系非线性分析方法

基于Winkler地基模型,推导了分层土中单桩处于线弹性和弹塑性状态的荷载传递矩阵,提出了单桩竖向位移内力非线性简化分析方法。考虑群桩中的"被动桩"与周围土体的相互"遮拦效应",对传统的桩–桩相互作用系数进行修正,并将其应用于刚性承台下受荷群桩和桩筏基础的非线性分析中。由于考虑了土体的成层性和桩土相互作用的非线性特性,计算模型更好地反映了土体的实际性状。计算结果与有限元计算值和试验结果进行对比分析,验证了本文方法的正确性,可应用于实际工程问题的分析。

Nonlinear analysis for settlement of vertically loaded pile foundation in layered soils

Based on the Winkler model,the load transfer matrixes of single pile in elastic and elasto-plastic state in layered soil were presented to obtain the simplified nonlinear method for analysis of settlement and internal force of single pile.The sheltering effect between passive piles and soil was taken into account to modify the conventional interaction factor between two piles.The approximate approach with the concept of the interaction factor was employed to study the nonlinear behavior of pile groups with rigid cap and piled raft foundation.Because the nonhomogeneity of soil and nonlinear interaction between piles and soil was considered,the theoretical model agreed with the fact quite well.The calculated results was compared with those of the finite element and field tests,and the feasibility of the proposed model for the analysis of pile groups and piled raft foundation was proved.