恒荷载作用下复合地基非线性分析

Nonlinear consolidation analysis of composite ground under constant load

从桩周土体径竖向渗流方程出发,采用土体e–logσ和e–logk半对数模型,对于排水桩桩体仅考虑竖向渗流并考虑涂抹区影响,建立恒荷载作用下复合地基非线性固结方程。通过与已有解的对比,证明此解析解的正确性。根据对复合地基非线性固结分析发现:复合地基固结速率随土体非线性参数Cc/Ck和荷载增量σ0/σsi的增大而减小,但相比Cc/Ck,荷载增量σ0/σsi对固结速率影响很小;随着桩土模量比增大,复合地基固结速率加快,且非线性参数Cc/Ck对固结速率的影响程度减小;排水桩复合地基固结速率受kh/kc即桩体渗透性影响很大。

Under a constant load,using the consolidation equation of soil including radial and vertical flow,considering influence of smear zone and nonlinear characteristic of soil,assuming that there is only vertical flow in grained pile,the governing equation is derived and its solution is obtained.The validity of the proposed method is confirmed through comparison among the existing analytical solutions.The analysis results show that:the consolidation velocity of composite ground decreases with the increase of Cc/Ck and stress ratio σ0/σsi,however σ0/σsi has less influence on the rate of consolidation in comparison with Cc/Ck;the larger the ratio of pile-soil modulus,the faster the consolidation velocity and the less influence of Cc/Ck on consolidation;the consolidation velocity of composite ground with grained pile is under great influence of the permeability of pile.