【摘要】 为实现回采工作面采前冲击地压危险性预评价,提出围岩波速结构的概念,其3个特征参量为:波速大小、波速梯度、波速异常区最小临巷距等。工作面冲击地压危险程度与煤层围岩的波速大小、波速梯度均呈正相关,与波速异常区最小临巷距呈负相关。建立基于煤层围岩波速结构特征参量的工作面冲击危险性评价模型,确定回采巷道冲击危险等级划分方法。采用地震波运动学理论,研究了煤层震源震动波在"老顶–直接顶–煤层"特殊层状结构中的传播特征,表明可通过回采工作面巷间地震初至波走时CT探测,来获取煤层围岩波速结构,用于分析整个煤岩组合系统的冲击危险性。将研究成果应用于古山煤矿069–2工作面冲击危险性预评价,评价结论以二维图像形式展现强烈冲击地压发生后的危险性分布状态,可用于指导针对性防冲措施的制订与实施。更多还原

【Abstract】 In order to achieve rockburst hazard pre-evaluation of working face,the concept of coal bed surrounding rock wave velocity structure is proposed,and its characteristic parameters are velocity size,velocity gradient,smallest distance of velocity anomalies to roadways,which are closely related to rockburst hazard. The rockburst hazard evaluation model based on characteristic parameters is constructed,and the classification method of rockburst hazard rating is determined. By kinetic theory of seismic waves,scoal source wave propagation characteristics in the special layered structure of roof-direct roof-coal seam are analyzed,indicating that velocity structure can be got by seismic first break travel-time CT technology. The research results were applied to working face 069–2 at Gushan coal mine. Practice shows that the evaluation results can be used for the formulation and implementation of protection measures.更多还原