Coal Mining and Designing Branch, China Coal Research Institute
CCTEG Coal Mining Research Institute
Shanxi Coal Caojiatan Mining Co. , Ltd.

针对浅埋厚硬顶板超大采高工作面矿压显现强烈的问题,基于支架工作阻力及现场微震覆岩监测数据,对曹家滩10m超大采高工作面矿压显现及覆岩活动规律进行了研究。研究结果表明:10m超大采高工作面基本顶初次来压步距为49.35m,周期来压步距平均为21.89m,动载系数平均为1.49;工作面存在“大小周期”来压现象,大周期来压期间,工作面来压步距显著上升。非来压期间支架工作阻力增大不显著,周期来压期间增阻显著,支架活柱有明显下缩,特别是“大周期”期间内,立柱平均下缩量和最大下缩量均值分别达到686.12mm和1321.35mm;超大采高工作面周期来压具有来压频繁、来压持续时间和来压步距长、动载矿压显现强烈、煤壁片帮剧烈等特点;微震事件活跃区域位于工作面倾向,距工作面中心0~130m,其中110~130m为峰值区。煤层顶板上40~60m微震频次低但能量高,是强矿压主导岩层。微震事件的时空分布规律与矿压规律吻合性较好,高能量微震事件通常先于工作面矿压显现发生,且与周期来压有较好的对应关系,对于矿压的预测可靠性或匹配度相对较高,高位岩层的架前切落是“大周期”来压强度显著增大和片帮冒顶的重要原因。

Aiming at solving the problem of strong mine pressure in extra thick mining face buried shallowly under thick and hard roof, based on support resistance and in - situ microseismic overlying rock monitoring data, the mine pressure and overburden movement in Caojiatan m super -high mining face were studied. The results show that the initial weighting interval of the main roof of the mining face is 49. 35 m, the average periodic weighting interval is 21. 89 m, and the average dynamic load coefficient is 1. 49. The working face has the phenomenon of “intense and mild periodic weighting”. During the intense weighting, the weighting interval increases significantly. During the non-weighting period, the working resistance of the support increases insignificantly, but significantly during the periodic weighting. The active column of the support has obvious shrinkage, especially during the intense weighting period, the average and maximum shrinkage of the column reach 686. 12 mm and 1321. 35 mm, respectively. It has the characteristics of long weighting interval, long weighting duration, frequent weighting, strong dynamic load mine pressure and severe rib spalling. The active area of microseismic events is along the working face dip, 0~130 m away from the center of the working face, and the peak area is in the 110~130 m area. At ~60 m above the coal seam roof, the microseismic events have low frequency but high energy, which is the dominant rock formation of strong mine pressure. The spatial and temporal distribution of microseismic events coordinates with the law of mine pressure. High-energy microseismic events usually occur before the mine pressure behaviors of the working face and have good correlation with periodic weightings, which is reliable for the prediction of mine pressure. The cutting and falling of high strata before the face support is the important reason for the obvious pressure increase and rib spalling during the intense weighting.

中煤科工开采研究院有限公司青年基金项目(KCYJY-2023-QN-05)

马镕山,徐刚,刘晓刚,等.厚硬顶板10m超大采高工作面覆岩运动与矿压显现规律研究[J].煤炭工程,2024,56(11):76-83.