Numerical modeling of confinement effects on failure pattern of brittle rocks

One of the most important goals of rock experiments is to determine deformation and strength of specimen under applying load, the status of failure condition is one of the subjects which can be used in soil mechanic and foundation engineering applications. To investigate the effect of confining pressure, the rock has been considered as bonded-particles method and simulated by particle flow code 3 dimensions (PFC3D). To compare numerical and experimental results, Young's modulus, Possion's ratio as well as maximum axial stress have been considered. The comparison of the numerical and experimental results of maximum axial stress and the Possion's ratio revealed good accordance. The initial number density of microcracks at the model was zero and increased while microcracking. In all uniaxial and triaxial tests with different confining stresses, the number density of microcracks during the failure remains almost constant which can be considered as a proof of failure occurring in the model.

Keywords:

Rock mechanic , Failure pattern , Confining pressure , Microcracking , Number density of microcracks