DYNAMIC FRACTURE PROCESS ANALYSIS OF ROCK SUBJECTED TO STRESS WAVE AND GAS PRESSURIZATION

摘要

The present paper proposes a new dynamic fracture process analysis that is able to simulate dynamic fracture process, considering the complexities of the interaction of stress wave and crack propagation, gas pressurization in the cracks, crack geometries such as crack opening displacement and crack length, etc. A conventional dynamic fracture process analysis based on the dynamic finite element and fracture mechanic is coupled with a developed finite difference scheme for gas flow through the fractures. A network model is used to combine the two analyses. In order to search the fractures connected with the blasthole, a crack search algorithm is devised. To consider the gas flowing through the fractures, the one-dimensional transient flow governed by conservation of mass and momentum and the detailed crack geometries for the gas flow are considered. The dynamic fracture mechanisms due to both stress wave and gas pressurization in blasting are investigated and discussed. To validate the proposed analysis, the predicted gas flow was compared with the observed gas flow due to the detonation of explosive.