Abstract:
The 3209 excavation working face of Fengjiata Coal Mine is taken as the background of research.Drilling hole peeping, theoretical analysis, experimental testing and on-site application are adopted to study the characteristics of mechanical parameters of surrounding rock in the 3209 working face, and a combined bearing arch structure with integrated anchor and grouting support in the advanced area is proposed.Based on cement-sodium silicate two-liquid quick-setting grouting material and pre-stressed diagonal grouting anchor cable, the stability control of the surrounding rock passing shallow buried zone is realized.Practical application shows that: the advanced grouting reinforcement of weathered soft rock roof by inorganic two-component quick-setting grouting reinforcing material can solve the problem of collapse-while-excavation for 3209 auxiliary transport roadway; Diagonal pulling anchor cable supporting construction of each row of 5 grouting anchors, with the grouting volume of 0.37 t/row, the effect of advanced reinforcing is excellent; With advanced grouting material filling up the surrounding rock fissure, and improvement of broken surrounding rock's bond strength, its integrity is enhanced; After the grouting reinforcement, the fissures of roof separating layer are filled densely, thus the integrity of the surrounding rock is boosted.