陕北矿区煤层开采地表下沉系数研究

Study on Surface Subsidence Coefficient of Coal Seam Mining in Northern Shaanxi Mining Area

为解决陕北矿区浅埋煤层开采地表下沉系数比较难确定这一问题,基于陕北矿区不同地形地貌条件下煤层开采的地表岩移参数的分析,得出了影响该矿区地表下沉系数的3个主要影响因素,即基采比JC、基载比JZ及坡体稳定性系数G。以JC、JZ为自变量,结合地形地貌以分段函数的形式,分别给出了地表下沉系数表达式。研究结果表明:黄土沟壑区地表下沉系数计算以基载比为主,且应考虑坡体高度与黄土覆盖层整体厚度的比例;沙土平原地区地表下沉系数计算以基采比为主,地表下沉量为水平地表下沉量。通过工程实例,验证了以基采比、基载比为自变量的地表下沉系数分段函数表达式的可靠性。

In order to solve the problem that the surface subsidence coefficient of shallow buried coal seam is difficult to determine in northern Shaanxi mining area,the data of surface rock displacement parameters in coal seam mining under different topographic conditions are collected in this paper.On the basis of analysis,three main influencing factors affecting the surface subsidence coefficient of the mining area are obtained,that is the ratio of bedrock thickness and overburden thickness JZ,the ratio of bedrock thickness and mining height JC,slope stability G.In addition to,taking JZand JCas independent variables and combining topographic forms with piecewise function,the expression of surface subsidence coefficient is given respectively.The research results show that the surface subsidence coefficient of loess gully region should be mainly calculated by JZ,and the ratio of the height of the slope to the overall thickness of the loess cover should be considered.The JCof the ground surface subsidence coefficient should be calculated at aeolian sandy site.Through two engineering examples,the reliability of the piecewise function expression of surface subsidence coefficient with JCand JZas independent variables is verified.