浅埋水工隧洞参数反演与安全影响评价

摘要

鉴于试验段工程地质条件复杂,现很难清晰地掌握主要土层特别是注浆加固土层的实际参数情况.基于隧洞施工过程中的动态监测数据,利用正交设计反分析方法对松散土层、注浆加固土层和初期支护的弹性模量进行了反演分析,并基于正交设计得到的最佳参数组合,评价隧洞开挖对既有燃气管线的安全性.反演得出的最佳参数组合为:初期支护的弹性模量为26000MPa,注浆加固土体为50MPa,松散土层为40MPa；浅埋水工隧洞开挖对既有燃气管线的影响较小,既有燃气管线处于安全稳定状态.%In order to know the mechanical effect and the stability of the adjacent gas pipeline, the optimum elastic modulus scheme of the loose soil, grouting reinforcement soil and primary support are back-analyzed with utilization of the orthogonal experiment design and on the basis of in-situ measured deformation. The safety impact evaluation on the gas pipeline during the construction process of the hydraulic tunnel are carried out with the back-calculated optimum parameters. The results show that the elastic modulus values for the primary support,the grouting reinforcement soil and the loose soil are 26000MPa, 50MPa and 40MPa,respectively. The adjacent gas pipeline was safe and stable during the construction process of the hydraulic tunnel.