富水全风化花岗岩蚀变带隧道施工技术

Tunnel Construction Technology of Water-rich Completely Weathered Granite Alteration Zone

新建玉磨铁路通达隧道DK115+900~956和DK119+120~183段处于全风化花岗岩蚀变接触带,在施工中易引发塌方、涌突等地质灾害,给施工进度和安全带来较大困难。结合通达隧道施工中蚀变带施工案例,通过加强超前地质预报、超前排水、注浆预加固围岩、优化开挖工法和管棚夹小导管超前支护等一系列措施,成功解决了因蚀变带引起的涌水、涌砂加固治理难题,确保了工程安全,保证了施工进度。

DK115+900~956 and DK119+120~183 sections of Tongda tunnel on Yumo railway are located in the completely weathered granite alteration contact zone,which is easy to cause geological disasters such as collapse and outburst during construction and brings great difficulties to the construction progress and safety.Combined with the alteration zone construction case in Tongda tunnel construction,through a series of measures,such as strengthening advance geological prediction,advance drainage,grouting pre reinforcement of surrounding rock,optimizing excavation method and pipe shed clip small pipe advance support,the problems of water gushing and sand gushing reinforcement caused by alteration zone are successfully solved,and the project safety is ensured,and the construction progress is guaranteed.