穿越山谷破碎地层浅埋隧道施工技术

Construction Technology of Shallow Tunnel Through Valley Fractured Stratum

穿越两座山间谷地的隧道覆盖层往往较小,形成浅埋隧道。由于山间谷地地层往往比较破碎且富水,围岩稳定性很差,隧道开挖后极易出现坍塌失稳,塌方甚至波及地表。采用地表袖阀管注浆技术对隧道周边松散围岩进行注浆加固,并在加固后钻取岩芯检查注浆加固效果。三维数值计算结果及台阶法施工过程中监测结果表明,采用地表袖阀管注浆加固地层有效提高了围岩的稳定性,保证了隧道施工安全。

Tunnels usually run cross valley with shallow cover.Because the stratum in mountain valley is often fractured and rich in water,the stability of surrounding rock is very weak,and it is easy to collapse and lose stability during tunnel excavation,or even collapse to the ground.In order to ensure the safety of tunnel construction,sleeve valve pipe grouting technology was used to reinforce soft valley ground,and the core was drilled to check the effect of grouting reinforcement.The results of three-dimensional numerical calculation and bench field monitoring show that the sleeve valve pipe grouting can effectively improve the stability of surrounding rock and ensure the safety of tunnel construction.