基于扩孔锚固的参数优化分析及力学性能试验研究

    Parameter optimization analysis and mechanical property test research based on reaming anchorage

    • 摘要: 针对软弱煤岩体锚固性能差、锚固力低的技术难题,提出采用锚固孔扩孔锚固的方法提高锚固力;采用数值模拟方法分析了钻孔围岩、锚固剂及锚杆的力学特征,并对扩孔参数进行优化分析;结合实验室树脂锚固剂的锚固效果试验,确定了扩孔段长度120 mm,最大扩孔直径58 mm为最佳扩孔参数,并研发了扩孔装置。实验室锚杆拉拔对比试验表明:扩孔锚固所能提供的抗拔力显著高于正常锚固,平均锚固力增大1.63倍,且在锚固剂与钻孔围岩脱粘后,锚固力衰减较小;扩孔段锚固体对钻孔围岩具有“压密-破坏-压密”的循环过程,表现出“延性破坏”特性,避免锚固力出现较大幅度的衰减。

       

      Abstract: Aiming at the technical problems of poor anchoring performance and low anchoring force of soft coal and rock mass, the method of inverted wedge reaming at the bottom of anchor hole is proposed to improve the anchoring force. The mechanical characteristics of surrounding rock, anchor agent and anchor rod are analyzed by numerical simulation method, and the reaming parameters are optimized. Combined with the anchoring effect test of resin anchor agent in the laboratory, the length of reaming section is determined to be 120 mm, and the maximum reaming diameter is 58 mm as the best reaming parameter, developed reaming device; the pull-out comparative test of the anchor rod in the laboratory shows that the pull-out resistance provided by the reamed anchor is significantly higher than that of the normal anchor, and the average anchor force increases by 1.63 times. The anchor force decays less after the debonding between anchorage agent and borehole surrounding rock. The anchor body in the reaming section has a cyclic process of “compaction-failure-compaction” for the surrounding rock of the borehole, showing the characteristics of “ductile failure”, avoiding the large attenuation of the anchoring force, and playing an important guiding role in solving the technical problems of roadway support in soft coal and rock mass.

       

    /

    返回文章
    返回