Experimental study on rock-like materials fragmentation by electric explosion method under high stress condition

High stress is the main feature of deep mining. The in situ stress plays a large part in rock fragmentation. In this study, an electric explosion system was developed to study the fragmentation behaviour of rock under high stress conditions. A series of test experiments, including electric blasting tests of copper wires in air and rock-like materials, and blasting crater tests under different stress loading conditions, were conducted. The dynamic evolution of the strain field, and crack propagation process during rocklike materials fragmentation were monitored by digital image correlation (DIC) technique. The results indicate: the electric explosion method is reliable and can provide a clean energy source for rock-like materials fragmentation. Besides, the static stress significantly affects the evolution of the strain field in specimens under electric explosion loading, and in turn changes the crack propagation behaviour, and the final shape and size of the fracture zone. (C) 2019 Elsevier B.V. All rights reserved.