第三系富水粉细砂地层固结圈施工技术

Construction Technology of Tertiary Water Silty-fine Sand Stratum Consolidation Ring

胡麻岭隧道第三系富水粉细砂地层原岩致密,但具有易扰动、扰动后快速软化的特性,传统的施工工艺,无法彻底的避免围岩的扰动。针对此现象,经过研究确定采用控制围岩周边精确扰动软化后常压注浆加固的方法。该项技术适合第三系富水粉细砂地质小断面斜井施工,工效高、进度快,施工成本大大降低,规避了该地质高压帷幕注浆时浆液难以扩散、或沿着随机大裂隙延伸的状况,能精确固结有效范围,保证后续施工稳定,对于正洞大断面第三系富水粉细砂施工也起到了一定的借鉴作用。

Tertiary rich water silty-fine sand stratum rock of Humaling tunnel is dense,but has the characteristic of easy perturbation and rapid softening,the traditional construction technology can not completely avoid the disturbance of surrounding rock. In view of this characteristic,the method of the pressure grouting after the precise perturbation of the surrounding rock and strengthening is？ adopted after study. This technology is suitable for the construction of the small section inclined well with Tertiary rich water and silty-fine sand geology,the construction efficiency is high,the progress is fast,the construction cost is greatly reduced,avoid the condition that slurry is difficult to diffuse in high-pressure curtain grouting,precisely solidify the effective range to ensure the stability of subsequent construction,also plays an important role in the construction of the tertiary rich water fine sand.