In order to study the deformation and failure law of roadway roof in soft and thick coal seam and carry out reinforcement support design, FLAC3D numerical simulation software was used to predict the failure of roadway roof, and roof drilling peeping was carried out in 1302 working face of No.3 coal seam in Sima Mine. The numerical simulation results showed that as the biaxial principal stress ratio rises and the maximum principal stress rotates, the plastic failure range and the maximum failure depth of the surrounding rock of the roadway increased, and the roof showed the alienation characteristics such as the penetration of the butterfly plastic zone, which was consistent with the peeping results. According to the results of numerical simulation and roof peeping, it was proposed to use high ductile anchor cable to suspend the broken rock mass to the stable rock layer, so as to inhibit the development of plastic zone, and at the same time, combined with the control countermeasures of shallow high density bolt support to prevent local roof fall.The application results showed that the deformation of the surrounding rock of the roadway in the test section tended to be stable in a relatively short period of time. As the roadway was affected by the mining of the working face, the active support effect of the anchor cable didn't fail, and the large deformation of the surrounding rock of the roadway was effectively controlled.
