Abstract:
The roadway of coal mine section mainly adopts wide coal pillar protection roadway, and wide coal pillar is easy to cause stress concentration, and cause problems such as large deformation of surrounding rock, rock burst, coal and gas outburst; on the other hand, the coal recovery rate of wide coal pillar protection roadway is low, resulting in a large number of coal resource loss. Small coal pillar protection roadway is easy to enter the state of plastic rupture, low bearing capacity and difficult to support. Neither waste of coal resources, and easy to support. Taking Jixiang Coal Industry
153103 transportation channel as the engineering case, the directional blasting of roadway surrounding rock drilling destroys the complete structure of the roadway surrounding rock, and the pressure is cut off to the small coal column, so that the peak support pressure transfers to the deep part of the roadway surrounding rock, the roadway is in the stress reduction area, and the roadway is easy to control. Through directional poly energy cutting and pressure discharge blasting, the small coal pillar can be protected and the coal recovery can be improved.