Feasibility study and prospects of rock fragmentation using ultrasonic vibration excitation

Abstract

This paper systematically examines the feasibility of using ultrasonic vibration excitation for rock breakage and fragmentation; it focuses on the failure mechanisms of rock mass under the impact of ultrasonic waves, and the development of ultrasonic technology. Laboratory testing using a self-designed system was conducted in this paper to further validate the efficiency and reliability of rock breakage using ultrasonics. The results show that: (i) under the effects of both the high speed impact of ultrasonic vibration excitation and induced rock vibration excitation, a fracture is initiated and propagates rapidly within and outside of the rock. Under ultrasonic vibration excitation for 140 s, the compressive strength decreased by 45.6%; (ii) under the excitation of ultrasonics, the rock specimens failed completely in a short time from inside to outside, and there are distinct fissures in the internal nucleation of the rock. It is suggested that ultrasonic excitation provides a novel and promising option for rock fragmentation and breakage, which optimises the efficiency of underground hard rock engineering.