基于微震监测技术的煤炭开采临断层区冲击矿压预测研究

Research on prediction of rock burst near fault zone in coal mining based on microseismic monitoring technology

煤炭开采临断层区冲击矿压的精准预测可有效增强矿区安全性。因此,提出基于微震监测技术的煤炭开采临断层区冲击矿压预测方法。假设煤炭矿区内煤岩材料的微元强度服从Weibull分布,构建冲击矿压非均质应变损伤软化本构模型以及煤炭开采临断层区冲击矿压的突变模型。利用开采区域内波速大小反演临断层区应力分布。将微震监测技术应用于冲击矿压突变模型中,建立冲击危险预警指标,利用冲击变形能指数获取冲击矿压空间域变化情况,实现煤炭开采过程中冲击危险区域以及能量聚散程度的预测。实例分析结果表明,该预测方法所获取微震监测系统台网监测数据将水平定位误差和垂直定位误差控制在20 m和50 m以内,证明该预测方法可准确预测煤炭开采临断层区冲击矿压。

The accurate prediction of rock burst near fault area in coal mining can effectively enhance the safety of coal mining area.Therefore,based on microseismic monitoring technology,the prediction method of rock burst near fault zone in coal mining is proposed.On the assumption of that the micro-element strength of coal and rock materials in the coal mining area is subject to Weibull distribution,the constitutive model of heterogeneous strain damage softening under rock burst and the abrupt model of rock burst near fault zone in coal mining are constructed.The wave velocity in the mining area is used to invert the stress distribution in the adjacent fault area.The microseismic monitoring technology is applied to the burst model of rock burst,the warning index of rock burst is established,and the spatial variation of rock burst is obtained by using the shock deformation energy index,it is realized to predict the danger area of rock burst and the degree of energy dispersion in the coal mining process.The case analysis result shows that the horizontal positioning error and vertical positioning error can be controlled within 20 m and 50 m with the monitoring data of microseismic monitoring system network obtained by the proposed method.It is proved that the prediction method can accurately predict the rock burst in the adjacent fault area of coal mining.