近距离下煤层开采顶板稳定性影响因素的数值模拟

Numerical Simulation of Factors Affecting Roof Stability of Lower Coal Seam Mining in Close Distance

以乌达煤田近距离煤层平错式布置开采为工程背景,采用数值模拟软件模拟了采空区下近距离下层煤开采时,综采面顶板稳定性与间隔层厚度和上层煤柱宽度之间的关系。研究结果表明,煤层间隔层厚度越小,对采场顶板稳定性影响越大,当间隔层厚度小于1 m时,顶板不能自稳,必须采取加固措施;上层煤层遗留煤柱宽度越大,下层煤上部的应力集中系数越小,而且遗留煤柱宽度对煤柱外采空区下顶板稳定性的影响范围相差不大。

The close-range coal seam mining in Wuda coalfield is used as the engineering background.The relationships between the stability of the roof and the main influencing factors such as roof thickness and upper coal pillar width were researched using numerical simulation method.The results show that the smaller the thickness of the coal interval layer,the more the influence on the roof stability of the stope,When the thickness of the interval layer is less than 1 m,the roof can not be self-stabilized,and reinforcement measures must be taken;the width of the coal pillar left behind in the upper coal bed is greater,the stress concentration factor on the lower coal is smaller,and the width of the remaining coal pillars has little effect on the stability of the roof below the coal pillars.