极近距离下位煤层回采巷道合理位置的确定

Determining Optimum Position of Roadway in Ultra-close Distance Seam

针对4-2煤层回采巷道布置这一难题,采用理论分析与数值模拟的方法分析了残留24 m煤柱的稳定性及其在底板的应力传递规律。研究表明:因4-1煤和4-2煤相距极近且24 m煤柱承受较大集中应力,故在煤柱下方3 m的水平截面上,处于煤柱正下方的垂直应力较大,应把4203主运顺槽布置在水平方向远离煤柱的应力降低区,即距煤柱中心线18 m的位置;最后,考虑支承压力传递影响角,确定4203主运顺槽巷帮距4-1煤煤柱边缘的距离为6 m,并经回采实践证明了回采巷道布置方式的合理性。

In view of the problem of roadway layout in 4-2 coal seam, the methods of theoretical analysis and numerical simulation are used to analyze the stability of residual 24 m coal pillar and its stress transfer law in the floor. Study shows that owing to the ultra-close distance between g_~ and 4-2 coal seam and the large concentrated stress on 24 m coal pillar, the vertical stress is larger on the 3 m horizontal cross-section below the coal pillar. Therefore, the 4203 haulage roadway shall be arranged in stress relaxed area which is away from coal pillar in the horizontal direction and the distance between its position and the center line of coal pillar is 18 m. Finally, with the consideration of the angle of abutment pressure transferring, the study determines the distance between the roadway position and coal pillar edge of 4-1 coal seam is 6 m.And the engineering practice proves the rationality of the layout of roadway.