Directional fracturing of granite cylinder via nitromethane-based energetic materials driven by electrical wire explosion
Authors:
Q Wang, Y Hu, M Zhang, Z Tao
Publisher:
AIP.org
Abstract:
The combination of electrical wire explosion and low sensitivity energetic materials is an efficient and practical method to generate controllable strong pressure waves, which is a potential alternative to explosives in directional fracturing applications. In this paper, a new configuration of hybrid load is proposed to generate synchronized pressure waves for directional fracturing, with the advantages of lower energy storage and smaller blast-hole diameters. The pressure wave of hybrid load explosion is measured, and the explosion synchronicity of the two loads at the microsecond level is verified by self-illumination images. Then, two-hole granite cylinders are used to verify the feasibility of directional fracturing, and the results show that the double loads explosion formed directional fractures connecting the two holes and a horizontal failure plane. The fracturing process, including fracture initiation, propagation, and connection, is recorded with a high-speed camera and is reproduced in numerical simulation. Based on the experimental and numerical results, the fracture morphology is characterized as four areas, and the fracturing mechanism is analyzed.
