为研究大同矿区特厚煤层采出空间大和远距离侏罗系煤层群重叠煤柱共同作用下的强矿压显现机制,采用通用离散元程序(UDEC)数值模拟方法,分析重叠煤柱作用下的工作面采动应力规律。应用高精度微震监测技术,得到侏罗系煤层群开采影响下的综放工作面覆岩运动与矿压显现的关系。研究表明,工作面回采至侏罗系煤柱对应区域时,工作面超前支承压力比在非煤柱区域提高了25%~33%;侏罗系煤柱重叠区域,在"煤柱-覆岩联动"和"煤柱-采动应力耦合"共同作用下,工作面矿压显现更为强烈;在临近采空区和侏罗系覆岩共同作用下,沿空巷道矿压显现强烈。工作面开采扰动、临近采空区覆岩运动和侏罗系重叠煤柱的耦合作用,是石炭系综放工作面矿压显现剧烈的根本原因。用提出的基于地面钻孔压裂重叠煤柱弱化的强矿压显现顶板控制技术,可削弱重叠煤柱对工作面开采的影响,减轻特厚煤层综放开采采场矿压的显现强度。
The paper was aimed at studying the strong strata behavior mechanism for the Datong mining area by numerical simulation and field measurement. Mining stress was analyzed by means of Universal Distinct Element Code (UDEC) numerical simulation software for the mining face under the effect of overlapping pillars. Using high-precision microseismic monitoring methods, the relationship between overburden strata movement and strata behavior was studied . The results show that mining face abutment pressure in the region Jurassic pillars correspond is higher, than that in non-coal pillar region by 25%- 33%, that in the Jurassic coal pillar overlap area, the strata behavior under the coupling effect of coal pillar-overburden linkage and coal pillar-mining stress is more intense, that under the combined action of mined-out area and Jurassic overlying strata, the ground pressure of gob-side entry is strong, and that the strong strata behavior of carboniferous mechanized mining caving face is induced by coupling action of mining disturbance, abutment pressure from mined-out area and Jurassic overlapping coal pillar. A technology was developed for controlling strong strata behavior.