Roadway Failure Mechanism and High Prestressed Supporting Technology in Soft Coal Seam With Composite Roof

For the problems that composite roof and low intensity on both sides in Chongsheng Coal Mine roadway, using the traditional shed style supporting is difficult to control large rock deformation. Based on the mechanical testing and roadway control theory, soft coal seam composite roof failure mechanism and high performance prestressed support system is revealed by using theoretical analysis and numerical simulation methods. Roadway chain instability and failure mechanism and its associated solution is explained. Industrial test shows that roof subsidence is 43 mm, the moved closer amount of the roadway is 115 mm, separation is less than 33 mm when the high performance prestressed supporting technology is used. Conclusion is that the high performance prestressed bolting can control the surrounding rock deformation of the composite roof soft coal roadway and improve the overall stability of the roadway.