Rock Strength Characteristics Based on Acoustic Testing

Abstract

In view of the characteristics of the complex composition and structure of coal rock whose strength has the discreteness, the wave velocity of coal rock specimen was measured by method of the ultrasonic pulse penetration. Meanwhile the relationship between the specimen wave velocity and mechanical parameters is obtained by regression analysis when using MTS815 testing machine for rock mechanics test. Results show that the strength differences of specimens which have similar wave velocity are small. Before the rock mechanics test, the wave velocity of specimens can be measured first. Then the strength of them can be expected and the specimens can also be classified according to the size of wave velocity, which will guide the rock mechanics test better, so as to provide a technical way for avoiding the blind trial from the discreteness of rock as far as possible.