Characteristics of discharge channel and its effect on concrete monolith splitting off by borehole electrical discharge blasting

Summary form only given. The method of concrete monolith splitting off by pulsed electrical discharge is presented. The pulsed power generator with stored energy up to 63 kJ and electro-explosive cartridge of polyethylene with wire for discharge initiation¹ are described. The electrical characteristics of plasma channel initiated by exploding wire in polyethylene capillary are investigated. The laboratory measurement results of current and voltage are presented. Calculations of resistance of plasma channel and dynamics of energy release in it are performed. A comparison of obtained characteristics with characteristics of free plasma discharge channel was made. It is shown that discharge channel bounded with capillary has more time stable resistance under permanent parameters of electrical circuit. It helps to initiate extensive discharge channel decrease energy losses in bars and cables of pulsed power generator which has primary importance in electrical discharge splitting off technology. It is shown that energy losses for free, middle bounded and hard bounded discharge was: 46%, 39% and 32% from stored energy respectively.