下伏采空区的寓仁隧道残余变形预测研究

寓仁隧道拟穿越太岳煤矿采空区的上覆岩层区域，该区域属于近水平煤层群，各工作面开停采时间较近且距离相近，不同工作面采空区产生的沉降变形共同影响隧道沿线安全，所以准确预测采空区残余变形对隧道的影响是保障隧道建设及使用安全的关键。本文采用变采厚概率积分法对山西省太岳煤矿不同停采时间的多个采空区在2020年后的残余变形量进行预测，并分析了采空区残余变形对寓仁隧道线路的影响。分析结果表明，新建寓仁隧道线路上的潜在的最大地表沉降量为366 mm，沿隧道方向最大残余水平位移为112 mm，垂直隧道方向最大残余水平位移为27 mm，最大残余倾斜变形为1.98 mm/m，最大残余曲率变形为0.033 mm/m2，均出现在隧道起点附近位置；新建寓仁隧道残余沉降量等变形量和工作面停采时间有一定相关性，停采时间越短变形数值越大，因此隧道长期稳定性受2205工作面影响较大；通过分析倾斜和曲率等参数，认为隧道有南北侧向坡度倾斜趋势及轴线受拉开裂或压缩隆起的复合变形。本计算结果可为隧道穿越采空区提供场地变形预测作为参考。

Research on residual deformation prediction of Yuren tunnel underlying goaf

Yuren tunnel is intended to cross the overlying rock area of Taiyue coal mining area, Taiyue coal mine is a nearly horizontal group mining seam, the mining age of each working face is similar and close to each other, the deformation generated by the goaf is large, which has a greater impact on the tunnel construction, so accurate prediction of the impact of the residual deformation of the mining area on the tunnel is the key to ensure the safety of the project. This paper adopted the probabilistic integral method of variable mining thickness to predict the residual deformation of several goafs of Taiyue coal mine in Shanxi Province with different stopping times after 2020. The analysis results show that the potential maximum surface settlement on the new Yuren tunnel is 366 mm, the maximum residual horizontal displacement along the tunnel direction is 112 mm, the maximum residual horizontal displacement in the vertical tunnel direction is 27 mm, the maximum residual tilt deformation is 1.98 mm/m, and the maximum residual curvature deformation is 0.033 mm/m2 all of which occur at location near the beginning of the tunnel. The long-term stability of the tunnel is greatly influenced by the 2205 coalface. By analyzing the inclination and curvature of the tunnel, it is concluded that the tunnel has a tendency of slope inclination in the north-south direction and a compound deformation of axial tension cracking or compression bulging. The results of this calculation can provide site deformation prediction as a reference for tunnel crossing the goaf.