Study on controlling law of fold structure on evolution of mining stress in deep mines

Aiming at the problems of stope stress and dynamic disaster caused by fold structure， the FLAC3D numerical simulation method was used to study the stress evolution law of the coal seam in the fold area， and the stress distribution characteristics of coal and rock at different positions in the fold area were analyzed.The study indicates:The horizontal stress concentration in the axis of anticline and syncline is caused by the folds formed by the overlying strata and horizontal compression， in which the internal arc pressure stress concentration in the anticline and syncline， and the external arc tensile stress concentration.When mining in the fold， the horizontal stress plays a major role in controlling.When the working face is close to the axis of anticline， the stability of roof rock gradually decreases， while the stability of floor rock gradually increases； if mining between the anticline and syncline， the abutment pressure is lower and the mining is safer when it is pushed from the axis of the anticline.The daily average energy of microseism increases when the No.7301 working face with depth of 1 000 m of the Zhaolou Coal Mine advanced in the fold near the syncline axis， and coal and roof breaking and falling occur when advancing to the anticline axis， which is in good agreement with the simulation results.The research results have certain guiding significance for safe mining in the fold area of stope.