| Summary: | The application of gob-side entry retaining(GER) in steeply dipping seam with hard roof has always been a difficult problem.Based on the characteristics of gangue slide accumulation in gob with steeply dipping seam, aim at make full use of the self bearing capacity of the gangue, the technology of the gob-side entry retaining with roof cutting(GERRC) in steeply dipping seam is proposed.Through the theoretical analysis and numerical simulation, the roof structures and surrounding rock stresses of the GERRC and the traditional GER were compared.According to the stability and deformation characteristics of roof in different stages of GEERC, the cutting angle and supporting technology were optimized, and field tests were carried out.This research finds that, when the roof structure of the GERRC is in a statically indeterminate state, it is more favorable for roadway stability.The stability of the surrounding rock in the dynamic section is the worst.Roadway strengthening support and blocking gangue support can be coordinated with the roof deformation.The field tests were successful.The cumulative deformation of the roof and floor is 177 mm.The supporting resistance of pillars is less than 28 MPa without obvious bending pillars.
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