# Axial Load Transfer Mechanism in Fully Grounded Rock Bolting System: A Systematic Review
## 4 Conclusions and Further Directions  
Rock bolting systems, particularly FGRBSs, are essential methods in mining, civil, and geotechnical engineering. They enhance rock mass stability, minimise deformation, and contribute to improved safety, budget, and faster project timelines. Regardless of the type, rock bolting systems develop forces in response to rock movement. The failure of FGRBSs can occur in different modes; however, bond failure at the B-G interface is widely recognised as the predominant failure mechanism. Understanding the axial load transfer mechanism forms the foundation for investigating interfacial shear behaviour in FGRBSs. To date, numerous laboratory tests have been conducted to characterise the behaviour of the B-G interface. The results indicated that the system's interfacial and axial response depends on the FGRBS's mechanical and geometrical characteristics, mechanical characteristics of great, geo-mechanical properties of the rock mass, and boundary conditions. Amongst these factors, bolt surface profile and group composition and mixture can be engineered and optimised for the preferable performance. The systematic reviews revealed that the effect of these factors has been investigated individually, e.g., the load-displacement behaviour, debonding capacity, or fracture propagation. Findings from experimental studies demonstrate that bolt surface configuration, e.g., rib angle, rib spacing, and rib width, impacts the axial behaviour of FGRBSs. The systematic review showed that there is a lack of understanding of the axial behaviour of FGRBSs in the corrosive environments. The authors found no research investigating the effect of preventative methods, such as sheathing, on the axial load mechanism of FGRBSs. The main challenge of applying such a preventative technique on FGRBSs is ensuring effective load transfer between the bolt, the grout annuli, and the rock or soils. Along with applying sheath, or sleeves, applying the fully grouted fibre rock bolts is another option in corrosive environments. The shearing mechanism of fully grouted fibreglass rock bolting systems and fully grouted sheathed rock bolts was investigated in a few identified research works. However, to the authors' best knowledge, few systematic studies have investigated the effect of using sheaths or fiberglass dowels on the axial load transfer mechanism of fully grouted bolts. As a result, it is recommended to focus on conducting future research works on developing experimental, analytical, and numerical analyses to contribute to a better understanding of the axial loading transfer mechanism in fully grouted sheathed/fibreglass rock bolts. Also, as discussed in the article, along with the importance of pull-out testing for measuring axial bearing capacity in FGRBSs which is well-established in the literature, machine learning (ML) and artificial intelligence (AI) are the other options which can offer promising approaches to accurately forecast the axial transfer mechanism within the FGRBSs. This could empower researchers and engineers to proactively identify potential reinforcement failures, leading to significant gains in research efficiency. Notably, ML methods hold great potential to enhance rock bolting research, particularly in areas directly related to the axial