超厚高位红层砂岩破断运动与矿震活动规律

The fracture and rockburst laws of high-position hard and extremely thick red beds

以鲍店煤矿十采区02工作面上覆200 m超厚高位红层砂岩为工程研究背景,分析建立了多工作面联合运动的超厚板力学模型,阐明了红层砂岩的损伤滑移破断规律,应用符拉索夫厚板理论,推导计算了红层砂岩的破断步距L=397.8 m。采用微矿震监测技术,分析验证了红层的破断规律及其动力响应特征。研究表明:未达到红层破断步距前,厚层砂岩板将在工作面平巷部位产生损伤,岩层仍处于稳定状态;工作面动力响应以小能级(小于105 J)的微震事件活动为主,在红层层位多发生在下表面。当红层悬露达到380 m时,初次破断运动;大能量(高于105 J)矿震事件频发,在平面上近似呈横向"O-X"型分布,在剖面上由红层下部逐渐向中部发展。红层最终呈现出四边铰接的稳定连续板状结构。

With the high-position hard extremely thick red beds of working face 02 in tenth section of Baodian mine as the engineering background, a mechanical model of extremely thick strata with composite movement of multi working faces was established, and the damage-slip fracture law of red beds was described. Through the theory of Vlasov, the fracture drawing pace of red beds, L=397.8 m was derived and calculated out. Through the monitoring analysis of microseism, the fracture law and dynamic response was analyzed and verified. The results have shown that before the red beds fractured, the strata will be damaged on the crossheading of two working faces, and the strata is still stable; the dynamic response is mostly occupied by the microseism under the level 105 J, and on the red beds it most concentrates on the lower surface. As the face advance gets 380 m, the red beds first fractured; the strong mining-induced earthquakes above 105 J frequently occur, distributed approximately like transversal ＂O-X＂in the plane, and developing from lower to middle on the section of red beds. Finally, the red beds will be stable as a form of articulated continuous plates.