厚土层厚基岩大采高综采面矿压规律

On Mine Strata Pressure Law for Fully Mechanized Face of Large Mining Height with Thick Bedrock and Alluvium

以小保当煤矿2-2煤层300 m埋深5 m大采高综采面地质条件为背景,采用理论分析和相似模拟相结合的方法,对厚土层厚基岩工作面上覆岩层结构、来压步距和支架工作阻力等进行研究.结果表明:2-2煤上覆岩层存在"双关键层"结构,亚关键层和主关键层共同作用导致工作面的大小周期来压现象,大、小周期来压步距分别为23,12 m.动载系数1.31,工作面来压较为剧烈.来压过程中支架工作阻力平均为12 643 k N,最大工作阻力为13 633 k N.工作面煤壁支承压力峰值为14.73 MPa,峰值位于采场煤壁前方5.5~20 m,支承压力增幅剧烈的区域为煤壁前方50 m范围内.小保当矿2-2煤厚土层厚基岩大采高综采面矿压规律与榆神府矿区近浅埋煤层矿压特点相似,为小保当煤矿2-2煤安全开采提供依据.

With the background of fully mechanized face of 5.0 m height and 500 m buried depth ofXiaobaodang 2^- 2 coal seam, and through the theoretical analysis and similar material simulation experiment, this paper analyzes the strata structure and weighting distance, etc. Results show that, there are two groups of key layer of overlying strata of the 2^-2 coal seam. The broken of the main key stratum and the secondary key stratum thus the roof weighting distance will be alternatively varied in size, that is 23 m and 12 m. The dynamic load coefficient is 1.31 and the intensity of mine pressure is more violent. During the roof weighting, the average support load and maximum support load are 12 643 kN and 13 633 kN. Dramatic increase region of abutment pressure is 50 m range in front of coal wall, abutment pressure peak value is 14.73 MPa and locates in the front of the coal wall 5.5？20 m range. The mine strata pressure law for fully mechanized face of large mining height with thick bedrock and alluvium of Xiaobaodang 2 2 coal seam has the similar mine pressure characteristics of near shallow seam in Yushen mining area. These parameters have provided scientific basis for safe mining of Xiaobaodang 2 2 coal seam.