Disintegration Of Rock By High Voltage Pulse Discharge

A high voltage 400 kV, 2.3 kJ pulse generator was used to produce discharges within rock specimens and cause their mechanical disintegration. Electrical parameters of the crushing pulse were measured to investigate the growth of the discharge process. The speed of growth of a breakdown channel through the rock structure was shown to be a strong function of the applied pulse voltage. Analyses of the energy consumption by a growing electrical breakdown channel as a function of the applied pulse voltage is presented. Presence of shock wave crushing is indicated by a number of small rock pieces chopped from the main surface, next to the end of the large cracks. A highly pulverized centre zone is also present indicating an explosive character of the crushing initiated by the discharge.