阿拉坦隧道竖向变形规律现场测试与分析

In-situ Monitoring and Analysis of Latan Tunnel Vertical Deformation Law

选取阿拉坦隧道浅埋段地表及拱顶上部围岩竖向位移为研究对象,进行实地监测并建立有限元数值计算模型,分析隧道浅埋段围岩变形规律。结果表明:掌子面施工对地表及岩层竖向变形影响范围主要集中在掌子面之前和之后0.5倍洞径(D)范围内,距掌子面1.8 D距离之后,其变形趋于稳定;横向比较各点测试结果得出,围岩松动圈已延伸至地表,离隧道中心线越远扰动强度越弱;数值计算得出岩层及地表变化规律与现场实测变化趋势大体相似。所得结论可为类似隧道工程施工过程变形控制提供借鉴。

The vertical displacement of the tunnel vault of Alatan tunnel was selected as the research object. The field monitoring was conducted, and the finite element numerical model was established. Then the deformation law of the shallow buried tunnel sur-rounding rock was analyzed. The results show that the influence of stope face construction on the vertical displacement of vault sur-rounding rock are mainly concentrated within the scope of 0.5D （diameter excavation）. The deformation becomes gradually stability at the distances from 1.8 times. The comparison results of the transverse measures points show that the surrounding rock loose circle ex-tends to the surface, and the farther from the center line of the tunnel, the less disturbance intensity. The strata and surface variation law of numerical calculation are consistent with the field measured. The research can provide a reference for the similar tunnel engi-neering construction of process monitoring..