Abstract Using the rock burst hazard of a railway tunnel in Southwest China as an example, a series of numerical simulation tests for rock burst characteristics were carried out based on the theory of particle flow and the PFC3D program, obtaining the microscopic failure characteristics of rock specimens under various stress paths. Combined with the results of a rock mechanics laboratory test, it was concluded that: 1) the Wet test showed that the condition for energy storage is sufficient in a granite rock section with a high probability of rock bursts of medium and high intensity; 2) the triaxial unloading test showed that intensive dilatation deformation can be generated in the unloading direction of the surrounding rock upon rock bursting and that the intensity of the rock burst can increase with the magnitudes of the confining pressure and unloading speed; and 3) the result of the PFC3D numerical simulation test went beyond expectations in respect to rock bursting and can be used as a new approach to replace some laboratory tests to perform further research on rock burst mechanisms and countermeasures.
Abstract：
Using the rock burst hazard of a railway tunnel in Southwest China as an example, a series of numerical simulation tests for rock burst characteristics were carried out based on the theory of particle flow and the PFC3D program, obtaining the microscopic failure characteristics of rock specimens under various stress paths. Combined with the results of a rock mechanics laboratory test, it was concluded that: 1) the Wet test showed that the condition for energy storage is sufficient in a granite rock section with a high probability of rock bursts of medium and high intensity; 2) the triaxial unloading test showed that intensive dilatation deformation can be generated in the unloading direction of the surrounding rock upon rock bursting and that the intensity of the rock burst can increase with the magnitudes of the confining pressure and unloading speed; and 3) the result of the PFC3D numerical simulation test went beyond expectations in respect to rock bursting and can be used as a new approach to replace some laboratory tests to perform further research on rock burst mechanisms and countermeasures.
2013, Vol. 50 