综放开采具有采高大、顶板来压运动剧烈等特点。物理模拟研究是目前矿山压力领域的主要研究手段之一,基于相似理论,通过制作相似模型对采场实际情况进行模拟,研究分析试验数据,掌握综放工作面顶板来压规律及采动覆岩运动特征,进一步指导矿山的安全生产。研究表明:工作面基本顶的周期运动呈“小-大-小”交错运动的规律,采动覆岩破裂高度与工作面推进距离呈S曲线发展规律;工作面煤壁前方塑性区内支承压力呈指数关系增加至压力峰值,弹性区内支承压力呈负指数关系降低至原岩应力。
Full-mechanized caving mining is of the characteristics of large mining height and violent roof weighting. Physical modeling is one of the important method to research mine ground pressure. The study simulated caving mining face with physical similar model based on similarity theory, analyzed the experimental data, gave the roof weighting law at the work face and the characteristics of mining overlying strata movement, so as to guide production safety in mine. The researched results showed that the periodic movement of main roof at coal mining face was appeared in the staggered motion of " weak- severe - weak". The fitted curve of the correlation between the fracture height of mining overlying strata and the advanced distance of working face developed in a S- shape. The abutment pressure in the plastic zone in front of the coal wall at working face would increase into its peak value in exponential distribution, while the abutment pressure in the elastic zone would decrease into the initial rock stress in negative exponential distribution.