The Risk Assessment And Control Technology For 1309 Coal Working Face In Dongtan Mine

In order to prevent the 1309 working face of Dongtan coal mine from rock burst during the excavation and production process,according to coal seam geological conditions and mining technology conditions,these research methods such as Engineering analogy,theoretical analysis and numerical simulation were used to analyze the main factors that leading to the occurrence of rock burst,to evaluate the rock burst dangerous level and to delineate hazardous areas The main contents of this paper are as follows:1)In order to provide the basis for analyzing the rock burst of 1309 working face and dividing hazardous areas,the paper analyzed the strata behaviors and microquake spatio-temporal evolution in the excavation of Dongtan coal mine 1303,1305 and 1307.2)Analyzing the hazard index of rock burst which have been influenced by coal seam and mining technical condition,and evaluating rock burst risk of working face.At the same time,the probability index of rock burst is given by using the diagnosis method of probability index.3)Considering the influence of face depth,adjacent goaf,geological structure,and roadway cross,the paper divided the impact area of each factor in coal-drilling and mining of 1309 working face.And then the multi-factor superposition method is used to superimpose the impact area,the dangerous zone and the danger level is given.4)According to risk levels of different area,microseismic monitoring method,cuttings monitoring method,and linear stress monitoring method,the paper proposes the rock burst monitoring scheme of working face driving and stopping.Meanwhile,the measures to prevention and control the rock burst are presented,such as the large diameter borehole unloading pressure,the blasting pressure of the coal body and the loose blasting of the bottom coal.5)For the mining conditions of 1309 working face,the management measures for the prevention and control of the impact of the working face are given.