Research on the reasonable parameter of softening hard roof with deep-hole blasting

摘要

Hard roof refers to rock of the high strength, large thickness, poor developed joint fissure, strong integrity, strong-self supporting capability.If mishandled, it often causes serious consequences.To solve this problem, a fully mechanized working face in Xinji is used as an example.In the FLAC3D numerical simulation, roof pressure and stress distribution is analyzed.Based on the analysis result, designing the hole interval of 30 meters, at the same time the hole angle, hole spacing and borehole parameter is designed.At last, the pressure on supports is measured.The result of the measure date analysis shows that the design effectively reduces the weighting interval, and the phenomenon of ground pressure is not strong.It works well for ensuring the safe and efficient production, and has a broad prospect of popularization and application.