Wang Shuai, Nan Hua, Qiao Jing, Wang Zhiming
School of Energy Science and Engineering, Henan Polytechnic University, Jiaozuo 454000, China.
Hami-Henan Energy Industry Research Institute, Hami 839000, China.
ACS Omega. 2023 Feb 24;8(9):8815-8826. doi: 10.1021/acsomega.3c00095. eCollection 2023 Mar 7.
This paper deals with the problem of the slippage failure of bolts in supporting soft rock, and the anchoring system being pulled out when conventional anchoring methods are used for bolts. This situation seriously threatens the safety of personnel and efficiency of work at the supporting soft rock. The main goal of this paper is to develop methods that will take full advantage of the potentially great supporting force that can be provided by bolts installed in soft rock. The study discusses the resin anchoring technique with reaming bottom and filling and proposes that replacing soft rock with high strength hard rock is an effective method to improve the anchoring force that prevents slip failure. The results of a comparative analysis of the different maximum diameters of reaming and the anchorage performance of the method using laboratory testing, numerical simulation, mechanics analysis, and field test are described. The results show that when the reaming diameter is less than five times that of the borehole, the anchorage force increases significantly. When the reaming diameter is more than five times that of the borehole, the increasing degree of anchoring force decreases obviously and the trend is gentle. The anchoring force of five times resin anchoring with reaming bottom and filling is 2.8 times that of conventional anchorage. The resin anchoring technique with reaming bottom and filling guarantees that bolts installed in soft rock will provide high supporting forces.
本文探讨了软岩支护中锚杆的滑移失效问题，以及采用传统锚固方法时锚杆锚固系统被拔出的问题。这种情况严重威胁到软岩支护时人员的安全和工作效率。本文的主要目标是开发出能够充分利用安装在软岩中的锚杆可能提供的巨大支护力的方法。该研究讨论了扩孔底部填充树脂锚固技术，并提出用高强度硬岩置换软岩是提高防止滑移失效的锚固力的有效方法。描述了通过实验室测试、数值模拟、力学分析和现场试验对不同扩孔最大直径与该方法锚固性能进行对比分析的结果。结果表明，当扩孔直径小于钻孔直径的5倍时，锚固力显著增加。当扩孔直径大于钻孔直径的5倍时，锚固力的增加程度明显减小且趋势平缓。扩孔底部填充树脂五次锚固的锚固力是传统锚固的2.8倍。扩孔底部填充树脂锚固技术确保了安装在软岩中的锚杆能提供高支护力。
