Expansion Of Microseismic Monitoring System And Seismicity In Stope Wall Rock In Dongguashan Copper Mine

Abstract:There are many new safety issues in the process of deep mining, such as impact ground pressure, rock burst, deformation and fracture of the roof and floor, pillar instability, but the seismicity is the most serious safety problem. Therefore, the research of seismicity has very important practical value and scientific theoretical significance. Relying on microseismic monitoring system construction projects of Dongguashan Copper Mine, the expanded sensor arrangement scheme of the mining microseismic monitoring system was studied, and microseismic activity of rock mass during excavation, seismic source mechanism solution of the deep rock failure were researched based on the object with deep stope. Main research contents and results are as follows:(1) The expanded sensor arrangement scheme of microseismic monitoring system was researched based on the existing microseismic monitoring system in the first mining area of Dongguashan Copper Mine, in which, the underground engineering specifications, the actual geological conditions, the location accuracy and sensitivity of monitoring system and the features of the old monitoring system were comprehensively considered.(2) Seismic activity in stope wall rock during the excavation was researched with the seismic data detected in Dongguashan Copper Mine. The results show that there is a positive correlation in time between the seismicity and the mining activities, and an obvious significant influence on each other between adjacent mining areas, and an obvious seismic aggregation from the point in time, for example, the seismic events increasing significantly during excavation blasting.(3) Based on the actual monitoring seismic wave signals from damage of surrounding rock in stopes of Dongguashan Copper Mine, the occurrence of surrounding rock failure plane were got through the inversion analysis of P wave initial motion with the seismic monitoring software JMTS, and consequently, the damage models of stope surrounding rock were researched. The inverse analysis of the moment tensor for the seismic wave signal around the stope was made. The analysis the failure mechanism of the stope wall rock was carried out with the decomposition according to an expansion center and pure double couple and a compensatory vector dipole. Combined with seismic source mechanism solution of the deep rock failure and the surrounding environment, the source models of three types of damage were proposed.