Research on Coal Pillar Width and Support Design of Gob-Side Entry

Coal pillar is a problem that cannot be ignored in coal mining, and reasonable width of coal pillar and support parameters can not only ensure the stability of roadway's surrounding rock, but also can extract more coal resources, save support cost. Based on the engineering background of 9106 working face mining in Linfen Tianyu Hengsheng Coal Industry of Wanbei Coal and Electricity Group, on the basis of analyzing the surrounding rock structure of gob-side entry, the theoretical analysis method was used to study the coal pillar width and support design parameters of 9106 gob-side entry. The results show that the width of coal pillar in 9106 gob-side entry section can be selected as 8.0, 9.0, 10.0 and 11.0 m. Considering the improvement of coal resource recovery and ensuring stability of surrounding rock of roadway, optimum sizes are 8.0 and 9.0 m. The roof of 9106 gob-side entry adopts the phi 20 x 2200 mm left-handed non-longitudinal reinforcement equal-strength screw steel bolt, and the row spacing is 1000 x 900 mm. The phi 18 x 1800 mm left-handed non-longitudinal reinforcement equal strength thread steel anchor was used in the side, and the row spacing was 1000 x 900 mm. The roof of 9106 gob-side entry adopts phi 17.8 x 5000 mm steel strand anchor cable, and the row spacing was 2000 x 1800 mm.