Surrounding rock control technology of gateway driven along goaf in fully-mechanized coal mining face

According to the engineering geological condition of gateway driven along goaf in No. 13218 fully- mechanized coal mining face of Xieqiao Mine,in order to reveal the migration status and difference of overburden strata structures above gateway driven along goaf with narrow coal pillars at different stage of whole service perio d,during gateway driven period,the overburden large structure formed by load support point of roof rock beam above gateway could ensure the self stability of gateway alon g goaf. During coal mining period,the overburden structure would not have stability lost and falling features. The FLAC3 Dsimulation software was applied to simulation on overburden stress distribution,surrounding rock deformation features and support mass stressed at different stage of gateway along the goaf. The optimization was conduct ed on different support parameters. The results showed that in comparison with previous support plan,with the applications of large extension rate and high strength thread steel bolt and small diameter anchor for roof reinforcement,bolt 1 steel mesh sidewall protection,floor corner bolt to prevent floor heave and other support technology,the pl astic zone scope of the surrounding rock in the gateway along the goaf was reduced from2.5m to 1. 4 m and the roof subsidence value was reduced from 620 mm to 430 mm. The optimized support plan could make the energy released and pressure yielded of surrounding rock and could ensure surrounding rock deformation controllable duri ng the driving of the dynamic pressure gateway with narrow coal pillars along the goaf and during the coal mining period.