Investigation of the Experimental High-Voltage Electric Pulse Fracturing of Rock with Capacitance as a Variable

The fracturing experiment of hard rock was carried out by self-designed high-voltage electrical pulse (HVEP) equipment. When the discharge voltage was 10 kV, the capacitance was increased from 20 to 500 mu F to increase discharge energy. The rock was fractured at discharge conditions of 10 kV and 500 mu F. Images of the fracture process of the rock were recorded. The action characteristics of HVEP are obtained by analyzing the current waveforms, strain curves, and vibration curves at different discharge energies. The increase in capacitance can enhance the current peak, strain peak, and peak particle velocity (PPV). Therefore, increasing the capacitance can achieve a stronger cracking effect. However, the discharge effect of HVEP does not always increase with the increase of capacitance. The rock will show obvious instability characteristics due to the appearance of cracks, including the prolongation of peak strain time and the acceleration of vibration decay rate.