Deformation Failure Featuresand Bolt Support Technology of Mine Gateway with Complex Roof

In order to solve the roof support problem of the mine roadway with complex roof in Xinzhi Mine, with the theoretical analysis, numerical simulation and t he engineering practices, a study on the deformation failure mechanism and the related bolt support technology of the mine roadway with the complex roof was conduct ed.The results showed that the deformation failure of the complex roof mainly was caused by the poor active support function of the bolt. The joint crack development of each stratum in the complex roof would cause high initial separation and deformation of the complex roof.Thus the stability of the roof would be getting worst continuou sly and finally would cause the high deformation and failure of the complex roof.Therefore, the pre-tension of the bolt (anchor) should be improved, the surface protectio n function of the support system should be enhanced and the anchor support strength should be increased in order to fully play the active support role of the bolt (anch or).