Numerical study of rock mechanical and fracture property based on CT images

In this paper, cracks with different angles are prefabricated in rock specimens to study the fracture characteristics of rock based on CT images. The rock specimens are prepared for compression tests according to the standard recommended by ISRM (International Society for Rock Mechanics). The effects of different angles on rock mechanical properties and crack propagation fracture modes are analyzed. Then, based on the cohesive element method and CT images, the relationship between porosity and Young's modulus as well as the fracture property is explored by the numerical modelling. In the modelling, the distribution of Young's modulus is determined by the CT image through the field variable method. The results show that prefabricated cracks reduce the mechanical properties of rock. The closer the angles of the prefabricated crack is, the greater the Young 's modulus of the rock sample is. The failure process of each specimen with prefabricated cracks is formed by the initiation and propagation of crack, and the angle of the prefabricated crack will affect the type of extended crack. As part of the numerical model proposed in this paper, the microstructure of rocks is reflected by CT images. The numerical results verify the effectiveness of the cohesive element method in the study of crack propagation for rock. The rock model in this paper can be used to predict engineering disasters such as collapse and landslide caused by rock fracture, which means that the methodology adopted in this paper is comprehensive and important to solve rock engineering problems.