为发展和完善煤岩动力破坏感应电荷监测技术及理论.以单轴压缩试验为基础.再认识了煤体破坏过程感应电荷变化规律与主控因素.提出了带电煤屑弹射过程的感应电荷产生机理,分析了感应电荷及其干扰信号的频域特征与影响要素.研究了感应电荷与煤体应力.应变能与变形破坏之间的定性关系.建立了受载煤体与感应电荷信号的损伤统计关系.分析了感应电荷与煤体能量的演化特征.进而提出了煤体应力与感应电荷的量化关系,研发了适用于井下复杂条件下煤岩电荷监测装备.在辽宁红阳三矿与河南平顶山十一矿开展了应用实践.分析了感应电荷与煤岩动力破坏.超前支承压力及巷道变形的相关性.结果表明:高幅值感应电荷信号产生的主因不是煤体的压电效应.而是煤体裂纹扩展.破裂面滑移摩擦与带电煤屑弹射的综合作用.特别是带电煤屑弹射到传感器时.感应电荷信号幅值将会突增,感应电荷信号以低频为主.干扰信号主频与外部供电网络谐波频率一致.但不同煤体的感应电荷信号主频分布范围存在差异,感应电荷强度与应力大小关系非直接相关.与应力非线性变化程度直接相关.特别是与应力降幅度呈正相关关系,感应电荷强度可直接反映煤体破坏程度.也可通过分析外载环境以及感应电荷信号和煤体损伤的统计关系.间接估算煤体应力,感应电荷强度与煤体弹性应变能存储量关系不显著.而与应变能耗散和释放量显著相关.即煤体破坏过程中耗散与释放能量越多.感应电荷强度越高.回采工作面支承压力影响区.高能微震频发区与巷道变形破坏严重区的感应电荷强度较高.说明感应电荷与煤岩动力破坏.超前支承压力及围岩变形具有良好相关性.可适用于井下动力灾害.采场来压与围岩稳定的监测预警.

To develop and improve the monitoring technology and theory of the charge induced by the failure of coal and rock,based on the uniaxial compression experiments,the laws of change and main control factors of induced charge signals in the process of coal failure are further investigated. The generation mechanism of induced charge in the process of charged coal chips ejection is proposed. The frequency characteristics and their influencing key factors of interference and effective signals of induced charge are analyzed. The qualitative relationship among the induced charge with the stress,strain energy and deformation failure is studied. The damage statistical relationship between the loaded coal and induced charge signals is established. The evolution characteristics relationship between the induced charge and coal energy is analyzed,and the quantitative relationship between the induced charge and stress of coal is proposed. The monitoring device of induced charge suitable for complex underground conditions is developed,and the monitoring practice is carried out in the Hongyang No.3 Mine of Liaoning Province and the Pingdingshan No.11 Mine of Henan Province. The correlation of induced charge on dynamic failure of coal and rock,abutment pressure and roadway deformation are analyzed. The results show that the piezoelectric effect of coal is not the main factor affecting the generation of high amplitude induced charge signals. The comprehensive effect of crack propagation,friction slip of fracture surface and charged coal chips ejection is the principal cause making the amplitude of induced charge signals high. In particular,the amplitude of the charge signals can suddenly increase when the charged coal chips are ejected into the sensor. The main frequency of interference signals of the induced charge is consistent with the harmonic frequency of the external power supply network,and the effective induced charge signals are mainly low frequency whose distribution range with different kinds of coal is different. The intensity of induced charge is not directly related to the magnitude of stress,but directly related to the degree of nonlinear change of stress,especially positively related to the amplitude of stress drop. The intensity of induced charge can directly reflect the damage degree of coal,and can also indirectly estimate the stress of coal by analyzing the external load environment and the statistical relationship between induced charge signals and coal failure. The relationship between intensity of induced charge and elastic strain energy of coal is not significant,but significantly related to dissipation and release of strain energy,that is,the more energy dissipated and released in the process of coal failure,the higher the induced charge intensity. The intensity of induced charge is higher in the area affected by the abutment pressure of face,the area of frequent occurrence of high energy microseism and the area of serious deformation failure of the roadway. It is shown that the induced charge has a good correlation with the dynamic failure of coal and rock,the advanced abutment pressure and the deformation of surrounding rock. The technology of induced charge can be used for the monitoring and early warning of underground dynamic disaster,stope pressure and the stability of surrounding rock.

1 煤体单轴压缩过程感应电荷再认识

   1.1 感应电荷信号频域分析

   1.2 感应电荷与应力.应变能及破坏之间关系

2 煤屑弹射过程感应电荷产生机制

3 煤体损伤破坏与感应电荷量化关系

   3.1 煤体损伤与感应电荷信号统计关系

   3.2 感应电荷强度与应力量化关系

4 井下监测实践

   4.1 红阳三矿监测实践与分析

   4.2 平煤十一矿监测实践与分析

5 结论