关键词: 近距离煤层群, 漏失量观测, 相似模拟, 覆岩破坏, 岩层破断角, 垮采比

Abstract: In order to study the law of overburden failure under condition of shallow buried depth and adjacent coal seams, 214201 working face of Hanjiawan Coal Mine was taken as the background, method of "ground drilling+leakage observation" and similar material simulation for overlying rocks have been carried out. By sorting out the measured data, the failure characteristics of overburden, development height of "two zones" of overburden and breaking angle of strata are analyzed under the geological and mining conditions. Measured results show that caving-height ratio is 6.5 for only 3-1 coal with insufficient mining, and 7.3 for only 4-2 coal. Similar material simulation show that caving-height ratio is 6.0 for 2-2 coal, 6.8 for 3-1 coal, and 5.8 for only 4-2 coal. Fracture angle of rock formation of 2-2 coal strata is 59.5~69°, that of 3-1 coal strata is 66~71° and that of 4-2 coal strata is 57~68°. Step spacing for the first time is 45m, and the periodic weighting length is 11~17m for 2-2 coal. Step spacing for the first time is 63m, and the periodic weighting length is 13~21m for 4-2 coal. Research shows that under condition of under condition of shallow buried depth and adjacent coal seams in Hanjiawan Coal Mine, only "two zones" are developed in the overlying strata, and the caving ratio of the lower coal seam is reduced, the caving ratio of the upper coal seam is increased, and the fracture angle of rock formation of the lower rock strata is reduced.