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

Yıl 2023, , 109 - 122, 20.10.2023

Soufı Amıne

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

Öz

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.

Anahtar Kelimeler

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

Destekleyen Kurum

UNIVERSITY MOHAMED V

Teşekkür

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,

Kaynakça

• Aziz, N., Majoor, D., & Mirzaghorbanali, A. (2017). Strength properties of grout for strata reinforcement. Procedia engineering, 191, 1178-1184.
• Barton, N., Løset, F., Lien, R., & Lunde, J. (1981). Application of Q-system in design decisions concerning dimensions and appropriate support for underground installations. In Subsurface space (pp. 553-561). Bieniawski, Z. T. (1973). Engineering classification of jointed rock masses. Civil Engineering= Siviele Ingenieurswese,(12), 335-343.
• Bieniawski, Z. (1988). The rock mass rating (RMR) system (geomechanics classification) in engineering practice. In Rock Classification Systems for Engineering Purposes. ASTM International. Kılıc, A., Yasar, E., & Celik, A. G. (2002) Effect of grout properties on the pull-out load capacity of fully grouted rock bolt. Tunnelling and underground space technology, ;17(4), 355-362.
• Komurlu, E., & Demir, S. (2019). Length effect on load bearing capacities of friction rock bolts. Periodica Polytechnica-Civil Engineering, 63(3).
• Li, C. C. (2017) Principles of rockbolting design. Journal of Rock Mechanics and Geotechnical Engineering; 9(3), 396-414.
• Li, S. C., Wang, H. T., Wang, Q., Jiang, B., Wang, F. Q., Guo, N. B., ... & Ren, Y. X. (2016) Failure mechanism of bolting support and high-strength bolt-grouting technology for deep and soft surrounding rock with high stress. Journal of Central South University;23(2), 440-448. Liu, J., Li, H., Li, Y., Yang, Y., Sun, T., Song, R., & Sun, R. (2021) Study on the Effect of Isotropic Initial Stress on the Anchoring Performance of Self-Expanding Bolts. Advances in Civil Engineering; 1-19. Wong, H. S., Zobel, M., Buenfeld, N. R., & Zimmerman, R. W. (2009). Influence of the interfacial transition zone and microcracking on the diffusivity, permeability and sorptivity of cement-based materials after drying. Magazine of concrete research, 61(8), 571-589. Zhang, Y., Li, X., & Liu, Y. (2017): Numerical simulation of the effect of water-cement ratio on the pull-out resistance of fully grouted rock bolts. Advances in Civil Engineering .