The analysis of rock damage process based on the microseismic monitoring and numerical simulations

Abstract

In mining process, the mechanical parameters of rock mass are deteriorating continuously. Fixed mechanical parameters were usually selected when using numerical simulation to analyze the damage process of rock mass, which led to the simulation results difficult to meet the actual situation. Microseismic monitoring system is an effective means to monitor the evolution of rock mass damage. It is of great significance to effectively combine the monitoring data with numerical simulation to correct rock mass parameters. In order to study the relationship between source parameters and rock mass damage, microseismic events of No. 15–16 exploratory line were analyzed from the project of Shirengou iron mine. Location verification was carried out on the established microseismic monitoring system and the microseismic events with larger errors were eliminated. The damage and failure characteristics of rock mass in this area were preliminarily analyzed based on the analysis of the temporal and spatial change of microseismic events and source parameters. In addition, based on the study of isotropic releasable strain energy, the damage model of rock mass was established by using the relationship between source parameters and releasable strain energy. The microseismic monitoring results were used as input of numerical simulation through FISH language existing in FLAC3D. Source parameters were used to modify rock mechanical parameters, so as to analyze the damage process of rock mass. Through the analysis of microseismic activity, the damage degree of rock mass and the change of plastic zone, the unstable areas were located, furthermore corresponding preventive measures were put forward.