复合地层盾构隧道掘进面稳定性与敏感性分析

Analysis on Stability and Sensitivity of Tunneling Face of Shield Tunnel in Composite Stratum

摘要:

现有文献极少有对盾构隧道开挖面特别是针对复合地层敏感性的研究。在极限分析上限法框架下，借助单纯形优化算法建立了复合地层盾构掘进面稳定性理论分析模型。通过将所提出理论模型与数值仿真结果对比验证了其有效性。随后，依托某盾构隧道工程穿越上软下硬两层土案例，分析了两层土摩擦角对盾构掘进面稳定性的影响；最后，基于Sobol序列构建了复合地层盾构掘进面全局敏感性分析模型，计算了两层土抗剪强度参数对盾构隧道掘进面极限支护压力的影响力指数。研究成果可为依托工程盾构隧道支护力设计提供参考。

Abstract:

Few studies have been conducted on the sensitivity of shield tunneling face, especially for the composite stratum. In the framework of the upper limit method in limit analysis, a theoretical analysis model for the stability of shield tunneling face in composite stratum is established by using the simplex optimization algorithm. The effectiveness of the proposed theoretical model is verified by comparing with the numerical simulation results. Subsequently, based on a case study of a shield tunnel project crossing the upper-soft and lower-hard soil layers, the influence of the friction angles of the two layers on the stability of the shield tunneling face is analyzed. Finally, based on the Sobol sequence, a global sensitivity analysis model for shield tunneling faces in composite stratum is constructed to calculate the influence index of the shear strength parameters of the two layers on the ultimate support pressure of the shield tunneling face. The research findings can provide a reference for the design of supporting pressure of the tunnel project.