基于力电耦合煤岩特性对煤岩破裂电磁辐射影响的研究
Research on the influence of coal and rock mechanic features on EME based on the coupling laws between EME and stress
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摘要: 为了有效地预测预报和治理煤岩动力灾害现象 ,在利用实验研究、理论分析和数值模拟方法研究煤岩变形破裂电磁辐射和应力耦合规律的基础上 ,研究了煤岩特性对煤岩变形破裂电磁辐射的影响。研究结果表明 :巷道掘进过程周围煤岩特性如体积弹性模量、内聚力和内摩擦角等对煤岩内部应力分布有较大的影响 ,应力峰值距离煤壁距离随着加载应力和采深的增加是逐渐增大的 ,应力峰值距煤壁距离随着煤岩体积模量、内聚力和内摩擦角的增加是逐渐减小的 ;随巷道两帮煤岩体积模量、内聚力和内摩擦角的降低 ,在监测点电磁辐射信号是逐渐减弱的 ,说明一方面是由于煤岩内部变形破裂程度降低即应力集中程度降低 ,另一方面是应力集中区距离监测点越远所致 ,力电耦合计算结果表明 ,通过监测电磁辐射信号的变化规律一方面可以来评价煤岩内部应力集中程度 ,一方面可评价煤岩动力灾害的危险性Abstract: For the purpose of predicting and controlling dynamical disasters of coal and rock efficiently, the influence of mechanical features of coal and rock on EME during the deformation and fracture of coal or rock is studied on the basis of the coupling laws between EME and stress by using experimental research, theoretical analysis and numerical simulation. The research results show that the mechanical features of coal and rock such as volume modulus, cohesion and internal friction angle around the roadway during the tunnel excavation have a great influence on stress distribution. The distance of peak stress away from coal wall increases with the increase of loading stress and excavation depth, and decreases with the increase of volume modulus, cohesion and internal friction angle. With the decrease of volume modulus, cohesion and internal friction angle of coal and rock around the roadway, the EME signals in the detected place will gradually become weak because of the reduction of the deformation and fracture of coal or rock.So according to the coupling calculated results, by detecting the EME signals we can estimate on the one hand the stress concentration degree and, on the other hand,the danger to dynamical disasters of coal and rock.