Enhancing the bearing capacity of friction anchor bolts through cementitious concrete injection for reinforced support in underground mine

Year 2023, Volume: 62 Issue: 3, 109 - 122, 20.10.2023

Soufı Amıne

https://doi.org/10.30797/madencilik.1312485

Abstract

Friction anchor bolts are commonly used for providing support in underground structures by relying on frictional forces between the bolt and the surrounding rock. This study proposes a method to enhance the efficiency of these bolts by injecting a cement-based mixture comprising cement, sand, and additives. The injection of this mixture into the bolt results in internal expansion, which reinforces the friction and bearing capacity of the bolt. The increased volume exerts a radial force, leading to improved adherence, load transfer, and void filling. Pullout tests were conducted on various rock masses to evaluate the performance of the anchor bolts. The results demonstrate increased pullout resistance with higher rock mass quality and longer cemented bolts. Additionally, the use of a silicate-based additive accelerated the curing time of the cement, enhancing the strength of the bolts. The study also highlights the significant influence of groundwater on the bearing capacity of the bolts. These findings indicate the effectiveness of cemented concrete injection in strengthening friction anchor bolts and their anchorage in underground structures.

Keywords

friction anchor bolt, cemented concrete injection, additives, pullout resistance

Supporting Institution

UNIVERSITY MOHAMED V

Thanks

Dear Editor, I kindly request your consideration for the publication of an article titled "Enhancing the Efficiency of Friction Anchor Bolts through Cemented Concrete Injection." The study explores a method to improve the performance of friction anchor bolts in underground structures. Friction anchor bolts are commonly used for support in underground structures, relying on the frictional forces between the bolt and surrounding rock. Our study proposes injecting a cement-based mixture with additives to enhance the efficiency of these bolts. The injected mixture results in internal expansion, reinforcing the bolt's friction and bearing capacity. To evaluate the method's effectiveness, we conducted pullout tests on various rock masses. The results demonstrate increased pullout resistance with higher rock mass quality and longer cemented bolts. Additionally, incorporating a silicate-based additive accelerated the curing time of the cement, enhancing the strength of the bolts. Furthermore, our study highlights the influential role of groundwater on the bearing capacity of the bolts, emphasizing the importance of considering hydrogeological conditions during implementation. Publishing this article would contribute to the field of underground construction, offering a promising approach to strengthen friction anchor bolts and improve their anchorage in underground structures. We hope this research will benefit the wider scientific community and inspire further advancements. Thank you for your time and consideration. Sincerely,

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