中国矿山工程

Severe deformation of surrounding rock in deep and large-section roadways affects the mining efficiency of coal mines. The main reason is that the burial depth increases and the surrounding rock stress is too large, which leads to the inability of traditional support measures to meet the requirements. For the above problems, the combined bolt-grouting technology is proposed for support, and two construction techniques of hollow grouting bolts are expounded. The numerical simulation method is used to analyze the stress and strain of the roadway surrounding rock under the traditional end bolt anchoring measure and the hollow grouting bolt anchoring measure. After the implementation of the on-site combined support measures, the effect is investigated, and the following conclusions are obtained: ① The ultimate pull-out stress of the end hollow grouting bolt anchoring is greater than that of the expanding hollow grouting bolt anchoring. The former is 1.5 times the ultimate pull-out stress of the latter; ② Numerical analysis shows that the traditional end bolt anchoring technology is used in the deep part. The maximum displacement of the roof is 140mm, and the roof is seriously damaged; For the hollow grouting bolt anchoring, the maximum displacement of the roof is 60mm; So the hollow grouting bolt anchoring technology has better supporting effect. ③ After comparison between the traditional support measures and the combined bolt-grouting support measures, it’s found that the maximum displacement in the deep part of the traditional bolt anchoring support area is 420mm, and the maximum displacement in the deep part of the hollow grouting bolt anchoring area is 120mm. The hollow bolt-grouting anchoring technology has obvious supporting effect. The research results show that the combined grouting-bolt support technology can effectively control the serious deformation of the surrounding rock in the large-section roadway.