Research Progress on the Load-Transfer Mechanisms of BFRP Anchors in Anti-Floating Systems for Building Foundations

Basalt fiber-reinforced polymer (BFRP) offers the advantages of high strength, excellent corrosion resistance, and low weight, providing a promising material solution to the durability problems associated with conventional steel anti-floating anchors. However, a systematic understanding of the interfacial bonding behavior, load-transfer mechanisms, and long-term evolution of BFRP anti-floating anchors remains lacking. Focusing on the interfacial bonding and load-transfer mechanisms of BFRP anti-floating anchors, this review systematically summarizes their structural configurations and the dual-interface system consisting of the BFRP anchor rod-anchorage body interface and the anchorage body-rock and soil mass interface. Particular emphasis is placed on the bonding mechanisms and typical failure modes of these two interfaces. The axial-force distribution along the BFRP anchor rod, interfacial shear-stress distribution, critical anchorage length, and their major influencing factors are also analyzed. Furthermore, the load-transfer and deformation characteristics under monotonic, cyclic, and sustained loading conditions are comparatively discussed. Existing studies indicate that load transfer in BFRP anti-floating anchors is markedly nonuniform and progressive. The axial force gradually decreases from the loading end toward the deeper anchorage zone, while the interfacial shear stress is concentrated within a limited load-transfer zone. With the progressive development of local slip and interfacial damage, the peak shear stress and effective load-transfer zone gradually migrate toward greater anchorage depths. The load-bearing capacity and failure mode are jointly governed by the mechanical properties of the BFRP anchor rod, the relative stiffness and strength of the two interfaces, the properties of the anchorage body, the confinement provided by the rock and soil mass, and construction quality. Cyclic and sustained loading further induce the accumulation of residual deformation, stiffness degradation, and stress redistribution. Future research should focus on long-term constitutive models and reliability-based design methods that account for coupled damage at the dual interfaces and environmental load-coupling effects.