大断面土质隧道施工方法的选择与施工期监测结果分析

Selection of construction method for large section tunnel in soil and analysis of monitoring results during construction period

本文以某大断面土质隧道施工为研究对象,通过对台阶法、弧形导坑法和中隔壁墙法三种土质隧道常用开挖方法的数值模拟结果的对比分析,确定了弧形导坑法为适合本工程的较优施工方法,进而结合其在隧道施工中的监控测量结果,得到了大断面土质隧道施工期间围岩及支护结构的应力发展规律和变形特性,为围岩稳定提供了可靠信息,保证了隧道施工的安全,并通过施工期实际监测结果与相应数值模拟结果的对比,验证了数值模拟结果的可靠性,为今后类似工程的设计和施工提供了类比依据。

Taking large-section soil tunnel construction as research background, the numerical simulation on three excavation methods for tunnel in soil including bench method, arch heading method and mid-wall method were carried out, and the arch heading method is confirmed as optimum construction method for this project by comparative analysis on the simulated results of the three methods. And then, according to analysis of monitoring measurement results of the construction being applied arch heading method, stress development laws and deformation characteristics of surrounding rock and supporting structure of large section tunnel in soil were obtained, which provide authentic communication on the stability of surrounding rock and guarantee for the safety in tunnel construction. Besides, the reliability of the simulated results is verified by comparing with monitoring measurement data, all of which offers analogical reference for design and construction in the future.