Modeling Micro-crack Coalescence in Marble Containing a Single Flaw Under Uniaxial Compression

Abstract

Due to the experimental limitations and the complexity of rock texture, the numerical simulation was employed to research the cracking process of marble sample containing a single flaw under uniaxial vertical compression. Parallel bond model (BPM), a type of bonded-particle model was used to represent the intact rock, while the smooth joint model (SJM) recently proposed has emerged as a promising tool for simulating the preexisting flaws. The two parameters of the flaw was considered in the paper, the flaw’s inclinations $\upbeta$ varied from 0° to 90°measured from the horizontal, and the flaw’s lengths ${\text{L}}$ varied from 10 mm to 80 mm. According to the position of the micro-crack, sequence to observe what is happening to crack initiation, propagation and coalescence. The progress was divided into two stages, the evolution of micro-crack and the stress distribution of the model were considered to adopt to analysis the failure progress of the model. Simulation results indicated that the flaw’s inclinations and flaw’s lengths showed an obvious effect on the unconfined compressive strength behavior of the sample. The flaw’s inclinations were changed the fracture angle of the model and the fracture mode of the model. The flaw’s inclinations There was a critical flaw length in the simulation between 30 mm and 40 mm of this sample, which distinguished the existing of flaw whether the main reason for the failure of rock.