Research on the Surrounding Rock Control Technology of Gob-Side Entry with a Narrow Coal Pillar Reserved in a Fully Mechanized Caving Face with Large Mining Height

II946 working face of Luling Coal Mine in Huaibei Coal Industruy Group was taken as research background to study the problems of roadway driven in stable coal bodies along the gob with a narrow pillar reserved. The position of the main roof fracture line in the gob was calculated through theory. The coal pillar mechanics model under the condition of large mining height was established and used to calculate the theoretical width of the narrow coal pillar. The side abutment pressure of the gob and the stress distribution and deformation characteristics of the narrow coal pillar of different widths were studied through FLAC3D numerical calculation and the reasonable width of the narrow coal pillar was obtained as 4 m. The deformation characteristics and failure laws of the surrounding rock of the gob-side entry in a fully mechanized caving face with large mining height were analyzed, and the support scheme was designed for the gob-side entry in large mining height. The stress and deformation laws of the surrounding rock and supporting structure of gob-side entry were analyzed by FLAC3D numerical simulation. Lastly the support results showed that the support scheme was reasonable and can ensure the stability of roadway.