帷幕注浆在阿尔金山隧道突泥涌水处治中的实践与思考

Practice and Thinking of Curtain Grouting in Treatment of Mud Bursting in Altun Mountain Tunnel

为解决全强风化花岗岩地质条件下突泥涌水突发性、灾害性的难题,依托柳园至格尔木国家高速公路(G3011)关键控制工程阿尔金山隧道,在传统帷幕注浆处治岩溶涌水、断层破碎带涌水技术的基础上,针对阿尔金山隧道高寒、高海拔自然条件下内燃机降效严重、注浆压力损失和水泥水化速度减缓、早期强度低等情况,结合全强风化花岗岩地层强度低、结构松散,水稳性差,在富水条件下极易崩解形成流塑体而发生突涌的特点,现场通过TSP、地质雷达和超前水平钻孔等综合勘察预报手段,实验确定新型注浆材料、压力与配合比,采取前进式、后退式和集束袖阀管注浆等帷幕注浆组合措施取得了较好的封闭固结效果,为隧道通过富水断层破碎带创造了条件,保证了项目的顺利实施。

This paper focuses on the sudden and disastrous problem of mud inrush and water inrush under the geological conditions of fully strongly weathered granite,which are common problems in the key control project of Liuyuan Golmud National Expressway(G3011)in the Arkin mountain tunnel.Altun mountain tunnel has high cold and high altitude,under the natural conditions,the efficiency of internal combustion engine is seriously reduced grouting pressure loss,slow cement hydration speed and low early strength under the natural conditions of high cold and high altitude.Based on the traditional curtain grouting technology for treating karst water gushing and water gushing in fault fracture zone,combined with the characteristics of fully strongly weathered granite stratum with low strength,loose structure and poor water stability,it is very easy to disintegrate and form flow plastic body under water rich conditions.TSP,geological radar,advanced horizontal drilling and other comprehensive survey and prediction methods are adopted on site and the pressure and mix ratio of new grouting materials determined by field tests.Combined curtain grouting measures such as forward,backward and cluster sleeve valve pipe grouting have achieved good sealing and consolidation effect,created conditions for the tunnel to pass through the water rich fault fracture zone and ensured the smooth implementation of the project.