Abstract:
In order to study the effect of loading rate on the failure characteristics and acoustic emission response of fractured sandstone, the prefabricated parallel cracked sandstone under uniaxial compression was simulated by using RFPA
2D numerical simulation software. And the mechanical characteristics, acoustic emission response characteristics and crack evolution law under different loading speeds are analyzed. The results show that with the increase of loading rate, peak strength, peak strain, rock bridge strength and rock bridge fracture strain of parallel fractured sandstone increase correspondingly. Peak AE counts also increase with the increase of loading rate. When the loading rate is low, the acoustic emission signals are abundant, and the fracture of the specimen is mainly shear failure along the prefabricated crack growth. When the loading rate is high, the final main crack is a tension crack parallel to the loading direction.