老河道下充分采动地表移动变形研究

针对1930煤矿河流改道后5#煤层充分开采后地表移动变形进行研究。通过理论计算得到地表下沉值为2803.56 mm,倾斜值为29.01 mm/m,曲率值为0.44×10~(-3)/m。基于相似理论进行相似材料模拟试验,取几何相似常数200、容重相似常数1.5、应力相似常数300按配比建立模型,共推进90步,每步开采2 cm。试验结果表明在开采结束后42 d内,地表移动变形速率最大,各变化曲线呈现出相对采空区中央布对称分布的规律,最大下沉值为2273.16 mm,最大倾斜值31.32 mm/m,最大曲率为0.43×10~(-3)/m。观测线实测数据与理论计算及物理试验结果相吻合,开采后形成的下沉盆地将威胁矿井安全生产。

Prediction of Surface Displacement and Deformation by Mining under Previous Riverway

The surface movement and deformation of the 5# coal seam after the diversion of the river in 1930 coal mine was studied.By theoretical calculation,the surface subsidence value is 2803.56 mm,the slope value is 29.01 mm/m and the curvature value is 0.44 × l0-3/m;Similar material simulation experiment was carried out based on similarity theory,and the model was established according to the geometric similarity constant 200,bulk density similarity constant 1.5,and the stress similarity constant 300,total 90 mining steps with each step 2 cm.The test results show that within 42 days after the end of mining,the surface movement deformation rate reached maximum,and the curves show a central symmetric distribution rule relative to mined-out area,with maximum subsidence 2273.16 mm,maximum tilt value 31.32 mm/m,and the maximum curvature 0.43 10-3/m.The measured data of the observation line are in agreement with the theoretical calculation and the physical test results.