Support Technology and Deformation Failure Mechanism of Roadway Compound Roof

In order to solve the problem of compound roof roadway support, the paper took No. 204 working face of Tingnan Mine No. 2 panel as a study object. Ac cording to monitoring roadway deformation, roof abscission layer, rock bolt load and test surrounding rock loose circle, analysis results showed that deformation and fail ure mechanism was divided into four stages, which included the compound roof structure bearing adjustment, the structure stiffness weakening, stress adjustment and t he structure instability or structure stable. Engineering geology, soft rock engineering mechanics and other multi-disciplinary theory were applied to analyse the compou nd roof failure mechanism and obtained the major reason of compound roof roadway failure, the beam-arch structure model was adopted to design the support of the CO mpound roof No.2 panel. Field applications showed that the tunnel roof convergence reduced 46. 5%, compared with the original support scheme, which restrained effe ctively the large deformation and failure of the compound roof.