煤岩体应力调整和破裂伴随弹性能的聚散并向外辐射震动波.通过震动波的能量特性可描述煤岩体的累积损伤以及弹性能集聚.综合两者可用于冲击地压危险的预测.研究了微震震动波的能量衰减规律.特别讨论了大尺度破裂下震动波能量对震源能量.半径.能量衰减系数以及受载点距震源距离的衰减响应规律.以甘肃某矿250106-1工作面微震实测数据为基础统计分析了不同震源能级的能量衰减系数分布规律,提出了基于震动波损伤效应的静载强度指标s以及描述弹性能集聚程度的动载强度指标d.基于动静载叠加原理构建了冲击危险的综合预测指标sd.并进行了预测实例分析.结果表明:250106-1工作面24起冲击事件统计结果说明其工作面超前300 m临空回采巷道为冲击发生的高风险区域,震源能量.半径.受载点距震源的距离对能量衰减的影响较大.而能量衰减系数的影响相对较小,预测实例分析结果表明s对冲击显现区域的预测效果较好.而对大能量事件的预测效能较低,d仅可对部分大能量事件进行预测.同时预测的冲击危险区域较广.侧面降低了d对冲击显现区域的预测效能,对于综合预测指标sd.大能量事件位于中等冲击危险区域的概率超过70%.并且冲击明显显现区域全部位于中等冲击危险区内.说明sd可有效预测大能量事件和冲击显现区域.预测效果较好.

The shock wave radiated from the coal and rock fracture causes dynamic load disturbance in the mining space.which results in cumulative damage of the coal and rock mass and elastic energy accumulation. It is easy to induce dynamic disasters such as coal burst under the combined action of the two aforementioned factors. This paper is focus on the seismic energy attenuation law of shock wave.especially under large-scale fracturing of energy to the source energy.radius.the energy attenuation coefficient and loading point away from the epicenter distance. Based on statistical analysis of recorded data from Longwall 250106-1 of a coal mine in Gansu Province.we got the distribution of energy attenuation coefficient of the different source level. The static load intensity index φs based on the damage effect of shock wave and the dynamic load intensity index φd describing the disturbance degree of shock wave were proposed.and the comprehensive prediction index of burst risk φsd was constructed based on the principle of static and static load superposition.in which a prediction example was analyzed. The results show that the statistical results of 24 coal bursts in Longwall 250106-1 indicate that the 300 m overhead gob side of the longwall face is the high-risk area. Source energy.radius and distance between load point and source have great influence on energy attenuation.while energy attenuation coefficient has relatively low effect. The prediction examples show that φs for the prediction effect of the coal burst area is ideal.but the prediction effect of the high-energy event is low. As for φd.Only part of high-energy events can be predicted.and the prediction of coal burst area is wide.which reduces the prediction efficiency of burst risk area. For the comprehensive prediction index φsd.the probability of high-energy event located in the moderate impact risk area is more than 70%.and the obvious coal burst areas are all located in the moderate impact risk area.indicating that the high-energy event and occurrence area of coal burst can be effectively predicted.which shows a good prediction performance.

1 工程实例背景

   1.1 250106-1工作面概况

   1.2 冲击显现概况

2 震动波能量衰减规律

   2.1 震动波能量衰减的理论模型

   2.2 不同能级震源的能量衰减系数特征

   2.3 震动波能量对不同因素的衰减响应规律

3 基于震动波能量衰减特性的冲击危险预测指标构建

   3.1 基于震动波损伤效应的静载强度指标

   3.2 描述弹性能集聚程度的动载强度指标

   3.3 综合预测指标的构建及计算流程

4 方法验证和实践

5 结论