Electromagnetic signal is a key means to monitor rock dynamic disasters. Its essential reason is the free movement of charges. At present, the variation law of microcurrents and the influence mechanism are still not clear in the loading process of rocks with different lithologies. Therefore, an electrical and mechanics experimental system of rock was established to explore the change rules of microcurrents generated in the loading process of rocks and the microscopic influence mechanisms. The research results showed that the microcurrent curves of different rocks had different change laws under low and high loading rates. At a low loading rate, the microcurrent was small and then increased exponentially. While the microcurrents went through three stages at high loading rates: rapid growth phase, gentle phase and mutation phase. The overall microcurrent level of marble was lower than granite and sandstone due to the lack of quartz. Quartz in the rock played a key role in current generation rate of loaded rock, but it was not a decisive factor. With a higher quartz content, the average current generation rate increased with the increase of grain size of the quartz crystal. Under the uniaxial compression of the rock, the piezoelectric effect and fracture power generation currents played the major role at different stages, and the piezoelectric-fracture synergy power generation mechanism was put forward. The research results could provide a theoretical basis for the mechanical influence mechanism of current generation during rock fracture process.

电磁信号是监测岩石动力灾害的关键手段。其本质原因是电荷的自由流动。目前，在不同岩性岩石的加载过程中，微电流的变化规律及其影响机制尚不明确。为此，建立岩石电力学实验系统，探索岩石加载过程中产生的微电流变化规律及微观影响机制。研究结果表明，不同岩石的微电流曲线在低负荷和高负荷下具有不同的变化规律。在低负载率下，微电流很小，然后呈指数增长。而微电流在高负载率下经历了三个阶段：快速生长阶段、温和阶段和突变阶段。由于缺乏石英，大理石的整体微电流水平低于花岗岩和砂岩。岩石中的石英对当前加载岩石的生成率起关键作用，但不是决定性因素。随着石英含量的增加，平均电流产生率随着石英晶体晶粒尺寸的增加而增加。在岩石单轴压缩作用下，压电效应和断裂发电电流在不同阶段起主要作用，提出了压电-断裂协同发电机制。研究结果可为岩石断裂过程中电流生成的力学影响机制提供理论依据。岩石中的石英对当前加载岩石的生成率起关键作用，但不是决定性因素。随着石英含量的增加，平均电流产生率随着石英晶体晶粒尺寸的增加而增加。在岩石单轴压缩作用下，压电效应和断裂发电电流在不同阶段起主要作用，提出了压电-断裂协同发电机制。研究结果可为岩石断裂过程中电流生成的力学影响机制提供理论依据。岩石中的石英对当前加载岩石的生成率起关键作用，但不是决定性因素。随着石英含量的增加，平均电流产生率随着石英晶体晶粒尺寸的增加而增加。在岩石单轴压缩作用下，压电效应和断裂发电电流在不同阶段起主要作用，提出了压电-断裂协同发电机制。研究结果可为岩石断裂过程中电流生成的力学影响机制提供理论依据。在岩石单轴压缩作用下，压电效应和断裂发电电流在不同阶段起主要作用，提出了压电-断裂协同发电机制。研究结果可为岩石断裂过程中电流生成的力学影响机制提供理论依据。在岩石单轴压缩作用下，压电效应和断裂发电电流在不同阶段起主要作用，提出了压电-断裂协同发电机制。研究结果可为岩石断裂过程中电流生成的力学影响机制提供理论依据。