Surrounding Rock Control Technology for Narrow Coal Pillar Roadway Excavation Along Goaf in Deep and Extra Thick Coal Seam

Aiming at the coal resource loss and mine pressure problems caused by the wide coal pillars retention in the deep and extra thick coal seam fully mechanized caving face of Xinjulong Coal Mine, this study takes the 1302 fully mechanized caving face as the object, deeply explores the applicability of narrow coal pillar roadway excavation along goaf technology in the deep and extra thick coal seam. Through on-site actual measurement data and theoretical analysis, the initial weighting step distance and periodic weighting step distance of the working face are determined. In view of the difficult problem of surrounding rock control brought by narrow coal pillar roadway excavation along goaf and top coal support in extra thick coal seam stoping roadways, a system of "anchor net belt cable support+advanced hydraulic prop support" is constructed, and a support scheme for the roof, solid side, and along goaf side of roadway retaining along goaf is designed. The practice shows that during the stoping period of the working face, the two sides displacement amount and the roof and floor displacement amount are both less than the designed maximum values. The effect of comprehensive control technology for narrow coal pillars and surrounding rock is good, meeting the engineering requirements and providing reference for safe and efficient mining of coal mines with similar geological conditions.