Technology of Controlled Blasting and Surrounding Rock Control for Mine Semi Coal and Rock Roadway

With the analysis on the surrounding rock broken causes of the mine semi coal and rock roadway in Dong baowei Mine, according to the blasting vibratio n and irrational support mode of the roadway heading operation, based on the surrounding rock features of the semi coal and rock roadway, a controlled blasting headin g of the semi coal and rock roadway and the "bolt/steel band/shotcreting" controlled technology of the surrounding rock was provided and the parameters of the blasting boreholes in the coal and rock were distinguished. The explosive loading was improved.Meanwhile the blasting heading could be met, the explosive loading could reduc e the blasting vibration to the surrounding rock and the disturbance radius in the surrounding rock could be controlled within 0.3 m.With the controlled blasting, the bolt support density would be reduced.With the shotcreting on the two side walls of the roadway, the support cost and the labor strength could be reduced.Thus the heading efficiency of the semi coal and rock roadway was improved by 40%.