Dynamic Sectional Control Technology for Surrounding Rock in Gob-side Entry Driving with Opposite Mining Direction

Taking the transportation roadway of No.3 upper 411 mining face which influenced by the mining activity dynamic pressure of No.3 upper 408 as study background, the numerical simulation of gob-side entry driving process of No.3 upper 411 transportation roadway in the opposite direction of No.3 upper 408 mining face was carried out. According to the stress monitoring results, the dynamic pressure tunnel is divided into three sections, and the dynamic sectional surrounding rock control is carried out: in the solid coal excavation section, bolt + steel mesh + anchor + beam combined support was provided, anchor cabled with parallel staggered three flower arrangement; in the section of strongly influenced dynamic pressure, on the basis of the solid coal excavation section, the support density is increased. In order to increase the integrity and the overall strength of the bolt, and the bolts of roof and two sides are connected by steel ladder with the diameter of 14 mm, anchor cabled with parallel staggered five flower arrangement; the influence of the dynamic pressure on the stable section is small, so bolt mesh shotcrete support is used to speed up the driving speed. Field monitoring verifies that the deformation of the gateway roof and floor as well as two sides of No.3 upper 411transport roadway were all not more than 200 mm, which controls the deformation of the surrounding rock of the dynamic pressure roadway effectively.