【摘要】 煤与瓦斯突出前兆信息的挖掘与定量描述是准确预测、预报该类灾害的前提和基础。为了研究煤与瓦斯突出的发生机制,挖掘煤与瓦斯突出灾害的前兆特征及其描述方法,开展基于微震监测的煤与瓦斯突出模拟试验研究。利用大型煤与瓦斯突出模拟试验系统和高灵敏微震监测系统,开展瓦斯突出全过程监测试验,有效收集了从突出孕育到发生完成全过程的微震动响应事件。微震信号的时、频域特征存在差异性和阶段性,并与瓦斯突出过程的孕育、准备、发生以及延续和终止4个阶段相对应。为了定量描述四阶段的特征,建立微震事件数N、事件发生率R、能量和Et以及当量能量E0等微震指标,这些指标表现出明显的阶段差异性。室内试验和现场监测研究表明,煤与瓦斯突出过程存在明显的阶段性微震特征差异,利用该差异性可以描述煤岩体内微震活动演化规律进而推断其稳定性状况,为灾害的提前预测提供依据。更多还原

【Abstract】 The foreboding information and quantitative description of coal and gas outburst precursors are the basis and precondition for hazard prediction. In order to research the occurrence mechanism and look for the precursors of coal and gas outburst,a laboratory investigation using microseismic system was carried out. A large-scale trials about coal and gas outburst had been set up,and the procedure was monitored by the high sensitivity microseismic system. The shaking triggering by coal instability and rupture process could be acquired by microseismic system,and the results shows that shaking signals distribution has obvious zoning characteristics in the whole process,including incubation period,emergence period and evolution period. For this purpose,the corresponding methods of hazard precursor quantitative description on the microseismic index were established. The indexes included N(number of events),R(event rate),E(energy) and BR(big event rate). The laboratory analysis and field measurement results show that the outburst process has obvious zoning features,and different stages have different signal features. It can be provided for the hazard prediction in advance,and be validated the occurrence mechanism further.更多还原