Study of Coal and Rock Floor Failure Characteristics of Upper Protective Layer Mining

摘要

For less study on coal rock floor fracture distribution of upper protective layer mining process, by numerical simulation and similarity simulation combined to get failure characteristics of distribution on the floor with the protective layer mining .divided into deformation-failure zone and plastic deformation zone of seam floor, with the same time divided each zone height of "upper three zone". Regional outburst prevention measures as the most effective, a mine protective layer mining practice, investigated the protective effect of the protective layer on the protected layer after mining coal seam gas pressure, gas content, permeability coefficient changes, Because of the protective layer at the plastic deformation zone of seam floor, the gas release have a good effect .By numerical simulation and similarity simulation test combined, get protective layer mining floor failure distribution.