坚硬顶板组合煤岩样破坏电磁辐射规律及其应用

The EME rules of composed coal and rock samples with hard roof failure and their application

采用实验室试验和分形理论相结合的方法研究了组合煤岩样变形破裂的电磁辐射规律。研究结果表明,加载初期,电磁辐射信号增加,然后略微减小,出现一段较为稳定的区域,当临近主破裂时,又大幅度增加,进入残余变形阶段时,电磁辐射又逐渐减小;电磁辐射信号与顶板在组合煤岩样的比例成正指数关系;电磁辐射脉冲数具有分形特征,并且随着加载进行,分形维数增加,临近主破裂时分形维数急剧减少;分形维数与顶板在组合煤岩样的比例成正线性关系。利用上述规律,成功地对7251工作面的冲击危险进行了预测预报。

The electric magnetic emission （EME） rules of deformation and failure of composed coal and rock samples are studied by lab experiments and fractal theory. The results show that at the initial stage of loading, EME signals increase, then decline slightly and stay at a stable level. Substantial increase appears when the composed coal and rock samples are close to the main fracture, and EME signals decline slowly when they are in the stage of residual deformation. The EME signals have a positive exponent relation to roof ratio in the composed coal and rock samples. The EME pulse count has the fractal characteristic, and the fractal dimensions increase with the process of loading. When the composed coal and rock samples are close to main fracture, the fractal dimensions decline suddenly, and it has a positive linear relation to the ratio of roof in the composed coal and rock samples. With the achieved rules, the burst danger has been forecasted successfully in face 7251.