Research on the Role of Control Hole in Deep-hole Pre-splitting Blasting in Outburst Coal Seams

摘要

Mechanical analysis model of blasting and controlling holes was set up combined with a gas outburst mine deep hole presplit blasting test, and the necessity of setting control hole in deep hole pre splitting blasting was analyzed. The theoretical calculation formula of hole spacing between the blasting and control hole was deducted based on explosion mechanics and elastic mechanics theory. The formula was applied in mine deep hole pre-splitting blasting parameters calculation, and can get the conclusion that hole spacing between the blasting and control hole can be increased to 6m. After the test found that the blasting holes gas drainage of average flow rate increased by 60 ~ 103%, and the average flow rate of the control holes gas drainage increased by 24 ~ 30%. The time of gas drainage was shortened and it can meet the need of mine production. It is indicated that the hole spacing between control hole and blasting hole up to 6m is appropriate.