Treatment technology for water and mud bursting of deep water rich sliding type weak zone on tunnel

Research purposes: DK 96+505~DK 96+530 paragraph of Liangshan tunnel on Xiamen-Shenzhen Railway developed water rich granite weak zone in which the length is 25 m, buried depth is 270 m. The weak zone is steeply inclined with a dip angle of 75 degrees to 85 degrees, and the two ends are complete granite. The lateral extension length of the weak zone is about 2.3 km. On March 14, 2009, when the tunnel excavated to the weak zone, water and mud bursting occurred, mud total is about 30 thousand m3, and siltation tunnel length is 230 m, resulting in surface collapse 200 m2 and pit depth of 20 m. Then set the circuitous heading at the left side of the tunnel, water gushing occurred again in the construction, the construction was blocked. Therefore, it is necessary to study the construction technology scheme to deal with the deep water rich sliding type weak zone. Research conclusions: (1) For deep water slide type soft with water and mud bursting, the comprehensive treatment scheme of drainage and pressure lowering, grouting reinforcement, advanced pipe shed is feasible. (2) For a large span tunnel, the Gaoyang construction method is adopted, the total deformation during construction is 2 mm, this method is safe and reliable, and the construction is relatively simple. (3) The research results can be used for the treatment of water rich sliding weak zone on tunnel. © 2015, Editorial Department of Journal of Railway Engineering Society. All right reserved.