基于p-y曲线分析隧道开挖对邻近单桩的影响  

Response of adjacent single pile due to tunnelling based on p-y curve

作　　者：章荣军[1] 郑俊杰[1] 蒲诃夫[1] 赵冬安[1] 

机构地区：[1]华中科技大学岩土与地下工程研究所,湖北武汉430074

出　　处：《岩土工程学报》2010年第12期1837-1845,共9页Chinese Journal of Geotechnical Engineering

基　　金：新世纪优秀人才支持计划资助项目(NCET-06-649);武汉市科技攻关计划项目(200860423194)

摘　　要：在分析隧道开挖对邻近单桩的影响时,基于Winkler地基梁模型的简化方法很难合理确定不同桩土刚度及地层位移条件下土体的等效参数。基于桩土界面非线性p–y曲线,提出了一种分析隧道开挖下邻近单桩响应的修正简化算法,结合有限差分原理,给出了非线性方程组的迭代法及增量法求解过程,同时将本文方法与既有研究成果进行了对比验证,并就相关问题进行了探讨。研究结果表明:在进行隧道开挖条件下邻近被动桩分析时,考虑桩土界面非线性特性是必要的,尤其是竖向;随着桩长增加,桩身在竖直方向上呈现出三种不同的受力性状;在cu/E p不变的情况下,桩身弯矩随着cu增加呈线性增长。When analyzing the response of adjacent piles due to tunnelling,the simplified method based on the Winkler foundation beam model has a defect that it is almost impossible to reasonably determine the equivalent parameters of soil under different conditions.In order to remedy this defect,a correction method based on the nonlinear p–y curve of pile-soil interface is proposed.Combining the finite difference algorithm,the solving process of nonlinear equations by using the iterative method and the incremental method is presented.Moreover,the results obtained by the proposed method are compared with those from other existing methods,and a further study on some relevant problems is made by means of parametric analysis.The results indicate that it is necessary to take the nonlinear characteristics of pile-soil interface into account when solving the ＂passive＂ pile problem,especially in the vertical direction.The pile sequentially shows three different mechanical characters in vertical direction with the increase of the pile length.Maintaining to be constant,the maximum bending moment of the pile increases linearly with increase of the undrained shear strength.

关 键 词：隧道开挖 邻近单桩 p–y曲线 弹性地基梁 迭代法 增量法 

分 类 号：U452[建筑科学—桥梁与隧道工程]