Numerical analysis of mechanical behavior of stratified rocks containing a single flaw by utilizing the particle flow code

Abstract

The evaluation of the mechanical properties of stratified rock masses with flaws is of great significance to geological engineering problems such as underground project and slope stability, etc. To investigate the mechanical properties of fractured stratified rock, the two-dimensional particle flow code (PFC2D) was used to conduct uniaxial compression simulation tests on stratified rock model containing a single flaw. To study the failure mechanism of the specimen, the stress-strain curve, acoustic emission events, mechanical parameters and cracking mode were recorded and analyzed. The simulation results showed that the stress-strain curves and AE events of specimens with different arrangements of flaw and stratification can be divided into three types, namely multi-peak type, pre-peak wave type and single peak with few fluctuations type. Inclined stratification caused the cracks to gradually propagate along the bedding planes, which weakened the strength and dominated the failure modes of the specimen. The flaw affected the stress distribution and played a role in connecting micro-cracks. The combined effect of stratification and flaw depended on the relative relationship between the stratification and the flaw, which determined the cracking path and failure modes.