煤与瓦斯突出激发阶段微震动态响应时频能谱特征

Coal and gas outburst is a severe persistent threat to mine safety. Coal and gas outburst pre-estimate is the key to control outburst. The subject study is planned to focus the trigger mechanism of coal and gas outburst. The study is based on series tests of coal body failure mecchanism by variable stress paths containing methane and physical model tests on coal and gas outburst. During the process of the tests,the tools on the microseismic dynamic response, stress&strain and gas flow with high degree of accuracy are adopted.The various stress paths are as follows:triaxial compression with the gas pressure variation,triaxial compression by gas seepage with the confining pressure variation and triaxial pre-peak unloading to investigate the process of elastic energy storage and failure evolvement. The theoretical principles are the non-linear and non-stationary signal analysis combined with failure mechanics and the hydrokinetics in the porous media. The dynamic response constitutive modules of damage and failure of the coal samples are planned to set up based on Wavelet and Hilbert-Huang Transformation time-frequecy energy spectrum. The microseismic time&frequecy analysis on outburst inoculation,activation and occurence is to be determined on the physical model tests with various load and various gas pressure, whose goal is to disclose the microseismic precursory signal to trigger coal and gas outburst. The relayional degree and the normalized feasibility,reliabilty of the Time-Frequency energy spectrum are demonstrated between the gas-coal damage mechanism and the innitiation stage of coal&gas outburst.The project will disclose the operating principle dynamically responsed by microseimicity on the precursory information released in the innitiation stage.It will afford firm and reliable foundation on the establishment of continuous and non-contact predition,prewarning index with micrioseismic dynamic response,which is planned to improve the pre-estimate accuracy of coal and gas outburst.

煤与瓦斯突出是煤矿生产的重大危害，预测、预警是防突的关键技术。本项目围绕煤与瓦斯突出机理这一核心课题，以激发阶段煤体所处压剪型破坏机制和煤与瓦斯突出激发特征为研究目标，采用应力、应变、流量和高灵敏振动加速度等多种测试手段，借助非线性、非平稳信号分析耦合损伤断裂力学、多孔介质流体动力学，进行含瓦斯煤的三轴压缩、渗流、卸围压和双剪等应力路径作用下微破裂和破坏力学特征试验，研究微震动态响应激发阶段含瓦斯煤的破坏过程小波、HHT时频能谱变化特征；模拟不同触发方式激发煤与瓦斯突出的灾变演化过程，研究突出4个阶段的微震动态响应小波、HHT时频能谱变化特征，论证含瓦斯煤的破坏和煤与瓦斯突出激发阶段之间的微震动态响应时频能谱特征的内在关联度和归一化的可行性、可靠度，揭示激发阶段所释放前兆信息的微震动态响应工作原理，为建立微震动态响应预警指标打下坚实、可靠的基础。

煤与瓦斯突出是煤矿生产的重大危害，预测、预警是防突的关键技术。本项目围绕煤与瓦斯突出机理这一核心课题，以激发阶段煤体所处压剪型破坏机制和煤与瓦斯突出激发特征为研究目标，采用应力、应变、流量和高灵敏振动加速度等多种测试手段，借助非线性、非平稳信号分析耦合损伤断裂力学、多孔介质流体动力学，进行含瓦斯煤的三轴压缩、渗流、卸围压和双剪等应力路径作用下微破裂和破坏力学特征试验，研究微震动态响应激发阶段含瓦斯煤的破坏过程小波、HHT时频能谱变化特征；模拟不同触发方式激发煤与瓦斯突出的灾变演化过程，研究突出4个阶段的微震动态响应小波、HHT时频能谱变化特征，论证含瓦斯煤的破坏和煤与瓦斯突出激发阶段之间的微震动态响应时频能谱特征的内在关联度和归一化的可行性、可靠度，揭示激发阶段所释放前兆信息的微震动态响应工作原理，为建立微震动态响应预警指标打下坚实、可靠的基础。