浅埋隧道开挖面破坏机理的非线性能耗分析方法与试验研究

项目名称： 浅埋隧道开挖面破坏机理的非线性能耗分析方法与试验研究

项目编号： No.51308072

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 建筑科学

项目作者： 黄阜

作者单位： 长沙理工大学

项目金额： 25万元

中文摘要： 我国的城市地下铁道在修建过程中经常出现由于开挖面失稳造成的地表塌陷事故，给人民群众的生命和财产安全带来极大的隐患。目前浅埋隧道开挖面稳定性分析中常用的线性破坏准则难以准确反映土体的非线性破坏特性，针对这一现状，本课题根据土体的非线性破坏特性对浅埋隧道开挖面的失稳机理展开了研究。通过构建浅埋隧道开挖面上限破坏机制，建立浅埋隧道开挖面的非线性能耗模型，得到浅埋隧道开挖面在临界状态下的支护力和破坏模式。分析开挖面的破坏特征，揭示极限状态下开挖面失稳发生机理和土体非线性参数对开挖面稳定性的影响规律，并利用数值模拟和离心模型试验对理论分析结果的有效性进行验证。本课题结合理论计算和模型试验对浅埋隧道开挖面破坏模式和失稳机理进行研究，为实际工程中浅埋隧道稳定性评估和支护结构优化设计提供了理论依据。

中文关键词： 极限分析上限定理；稳定性分析；非线性破坏准则；变分法；破坏机理

英文摘要： The surface subsidence accidents caused by instability of the front of a tunnel driven in shallow strata occur frequently, which will threaten to people's life and property. However, the linear failure criterion commonly used in face stability analysis of shallow tunnel is hard to reflect the nonlinear failure characteristics of soil. Thus, the failure mechanism of a shallow tunnel face is investigated on the basis of the nonlinear failure characteristics of soil in this study. By constructing an upper bound failure mechanism, the nonlinear energy consuming model of shallow tunnel face was established and the supporting pressure and failure mode of shallow tunnel face at critical state were obtained. Furthermore, the failure mechanism of tunnel face at limit state and the influence of soil nonlinear parameters on tunnel face stability were revealed. To evaluate the validity of the theoretical analysis, the results of theoretical analysis were compared with the numerical simulation and centrifugal model experiment results. Combining the theoretical calculation and centrifugal model experiment, the failure characteristic and failure mechanism of shallow tunnel face were studied, which provided theoretical foundation for stability evaluation and supporting structure optimization design of shallow tunnel in practica

英文关键词： upper bound theorem of limit analysis；stability analysis；nonlinear failure criterion；variational approach；failure mechanism