A study of high-intensity high voltage electric pulse fracturing - A perspective on the energy distribution of shock waves

Abstract

High voltage electrical pulse is regarded as a new fracturing technology. High voltage electrical pulse under electro-hydraulic conditions produces shock waves to destroy an object. However, the energy generation mechanism of shock waves is still unclear. In this study, image evolution and vibration time-frequency analysis are used to analyze the fracture mode and shock energy action mode of concrete. The high voltage electrical pulse fracturing process produces an intense flash of light. The rise in voltage leads to an increase in peak particle velocity and maximum amplitude. The discharge conditions for concrete fracture were 12 kV and 500 μF. The peak shock waves vibrational energy occurs in the time domain near 0 s, and at a frequency of 1.07 Hz. The energy of shock waves is concentrated in the frequency domain from 0 to 100 Hz. When concrete fractures, the energy of shock waves is shifted in the frequency domain from 0 to 10 Hz. The difference of amplitude integral is 276.14 when the voltage rises from 8 kV to 12 kV.