Rockburst is one of the disasters can occurr in deep mining and rock excavation. It is a kind of dynamic fracture excited by the released elastic energy previously stored in the rock mass. The elastic energy releasing is correlated to the post peak behavior of the excavated rock mass. On the other hand

the rockburst phenomenon is also correlated with the excavation rate. A numerical modeling for rockburst is presented. The modeling is based on the complete stress-strain behavior of rocks obtained in laboratory. The post peak stress-strain behavior is specially considered in the analysis. Furthermore

the influences of loading rates are also included. The excavation process of a tunnel in rock mass is simulated in the study. The fracture development and the elastic energy releasing rates under different loading rates are computed in the simulation. The computed results indicate that the fracture is likely to initially occur near the rock surface and then propagate towards the internal zone of the rock mass. It is also demonstrated that rockburst is more likely to be occurred under a higher excavation rate than that under a lower excavation rate.