陈家坡隧道出口滑坡稳定性分析与治理措施研究

Stability Analysis and Control Measures of the Landslide at the Exit of Chenjiapo Tunnel

为了保障陈家坡隧道的正常施工和后期的安全运营。根据工程地质调绘、钻探及室内试验结果,分析了陈家坡隧道出口已滑滑坡体和不稳定斜坡体的稳定性,并提出了相应的滑坡治理工程措施。结果表明:隧道出口滑坡段存在三条隐伏压扭性正断层。出口已滑滑坡体体积约62,700 m3,不稳定斜坡体体积约869,000 m3。在暴雨工况下,已滑滑坡体和不稳定斜坡体稳定性系数分别为0.968~0.982和1.049~1.084,处于不稳定和欠稳定–基本稳定状态,隧道施工基本停止。对陈家坡隧道出口滑坡采用设置15根长16 m^32 m的钢筋混凝土抗滑桩作为主支挡,在桩前设置仰斜式排水孔、渗沟、封闭坡体裂缝等为辅的滑坡综合治理措施,为类似工程提供参考和借鉴。

In order to ensure the normal construction and safe operation of the Chenjiapo tunnel in the later period,based on engineering geological mapping,drilling and laboratory test results,the stability of sliding and unstable slopes at the exit of Chenjiapo tunnel is analyzed,and corresponding engi-neering measures for landslide control are put forward.The results show that there are three concealed compressive-torsional normal faults with lithologic fracture in the landslide.The volume of the landslide body at the exit is about 62,700 m3,and the volume of the unstable slope body is about 869,000 m3.Under rainstorm conditions,the stability coefficients of sliding landslide and unstable slope are 0.968-0.982 and 1.049-1.084 respectively.They are in unstable and unsta-ble-basically stable state respectively,and the tunnel construction is basically stopped.Fifteen 16-32 m long reinforced concrete anti-slide piles are used as the main support for the landslide at the exit of Chenjiapo tunnel,and elevated drainage holes,seepage ditches and cracks in the slope are set in front of the piles as supplementary measures for comprehensive landslide control.It provides reference for other similar projects.