Research on the Influence Rule of Ultrasonic Vibration Time on Granite Damage

The method of theoretical analysis, finite element numerical simulation and experimental research were used to explore the damage and the strength degradation law of granite under ultrasonic vibration over time. It is of great significance to improve the effect of rock crushing, and to provide theoretical guidance for the application of ultrasonic vibrators in hard rock drilling and development of ultrasonic vibration rock drilling. The finite element method is used to establish the practical heterogeneous rock model to analyze the law of rock crack propagation in different time periods, and the ultrasonic vibration time threshold is proposed to provide theoretical guidance for the experiment. The porosity and strength of the rock samples are measured by nuclear magnetic resonance and uniaxial compressive strength after vibration. The influence of vibration time on rock damage is analyzed.