木寨岭隧道高地应力软岩大变形施工技术

摘要

During the construction of Muzhailing tunnel, high ground stresses of soft rocks caused large deformations and damages of primary support. In order to guarantee smooth and safe construction, measures such as multiple support, deformation allowances, stress releasing, stiffness increasing of secondary lining and supershort step excavation were adopted which effectively controlled the large deformation of surrounding rocks. This paper introduces the projcct in general, large deformations during construction and countermeasures as well as their effect inspection in Muzhailing tunnel.%木寨岭隧道施工中受到高地应力软岩地质的影响,初期支护多处出现大变形,破坏严重.为了保证顺利安全施工,采用了先柔后刚、先放后抗、多重支护、预留变形量、应力释放、提高二次衬砌刚度和超短台阶开挖等措施,有效控制了围岩大变形.文章主要介绍了木寨岭隧道的工程概况、施工中出现的大变形情况,以及控制大变形的各项措施和效果检验.