含瓦斯煤受载损伤演化声发射特性实验研究

Experimental study on characteristics of acoustic emission for coal containing gas damaged evolution under loading

搭建了含瓦斯煤单轴压缩信息采集系统,测试了煤样受载破坏过程中声发射及力学特性参数的变化,并对煤岩损伤演化模型及声发射特性进行了深入的分析研究。研究结果表明,含瓦斯煤在受载破坏过程中能够产生声发射信号,在受载前期声发射信号较少,受载后期较多,载荷峰值附近声发射信号达到最大值;声发射脉冲数及能量与载荷的变化趋势一致,能够直观地反映含瓦斯煤损伤程度;基于声发射特性参数的损伤演化模型,根据声发射脉冲数及能量所计算的损伤值与实测值变化趋势基本一致;作为前兆信息,声发射信号能够表征煤岩损伤演化规律,反映煤岩受载破坏状态。该研究成果将为现场煤岩瓦斯动力灾害的监测及预防提供参考。信号能够表征煤岩损伤演化规律,反映煤岩受载破坏状态。该研究成果将为现场煤岩瓦斯动力灾害的监测及预防提供参考。

An information collection system of coal containing gas under uniaxial compression was built,dates’ change of acoustic emission and mechanical parameters while coal samples loaded were tested,and damaged evolution model of coal and rock and characteristic of acoustic emission were studied deeply.The research results show that there are acoustic emission signals produced during loaded process for coal containing gas.The number of acoustic emission singles is less at early stage and more at later stage,while achieves the maximum value when the load reaches peak value.The change trend of pulse number and energy of acoustic emission is consistent with the load value,which can reflect damage degree of coal containing gas well.Based on the coal damaged evolution model of acoustic emission characteristics parameters,change trend of damage value calculated from the acoustic emission pulse number and energy and the actual measured value are basical identical.As a precursor information,the acoustic emission signal can represent damage evolution laws of coal and rock and reflect damage state under loaded state.The research result would provide reference for monitoring and preventing of gas dynamic disaster of coal and rock in coal mine.