Numerical simulation of progressive rock failure and associated seismicity

In this paper, a numerical approach to modeling progressive failure leading to collapse in rock and associated seismicity is reported. In the first part, a newly developed numerical code, RFPA(2D) (Rock Failure Process Analysis), is introduced. The program allows modeling of the observed evolution of damage and associated seismic events due to progressive failure leading to collapse in brittle rock. There ave three features distinguishing the approach from conventional numerical methods such as FEM: (1) bq, introducing heterogeneity of rock parameters into the model, RFPA(2D) can simulate non-linear behavior in rock using a linear method; (2) by introducing elastic modulus reduction for failed elements, RFPA(2D) can process discontinuum mechanics problems by a continuum mechanics method; and (3) by recording the event-rate of failed elements, the seismicities associated with the progressive failure in rock can be simulated. In the second part of the paper, the applications of RFPA(2D) in simulating geological process and in solving mining design problems are illustrated. Numerical simulation of a fault initiation process indicates that some of the important phenomena, such as coalescence of microfracture, the nucleation and growth of crack clusters, fault initiation and development, elastic rebound, dilatation, uplift and seismic behavior, etc. can be simulated with this numerical code. The simulation of progressive failure leading to collapse in underground openings demonstrates the capacity of this code in solving mining design problems. (C) 1997 Elsevier Science Ltd.