Abstract: WT5,5BZBy study of the mechanical characteristics of fault rocks, the authors consider that the water bursting is an instant aneous geologic event under a combined effect. The process before water bursting acts as a geological activation related to time of exploitation. The geological process and the instancy of water bursting correspond to multi factors: rockmass elastic deformation, damping deformation, steady state flow deformation, and accelerated flow deformation. So the water bursting has time effect characteristic.