Soda residue (SR), a waste by-product of sodium carbonate production, occupies land resources and pollutes the environment seriously. To promote the resource reusing of waste SR, this paper studies the feasibility of utilizing SR for the preparation of soda residue soil (SRS) through laboratory and field tests. The SR and fly ash (FA) were mixed with six different proportions (SR:FA is 1:0, 10:1, 8:1, 6:1, 3:1, 1:1) to prepare SRS, and the optimum water content, maximum dry density, shear strength, and unconfined compression strength of the SRS were measured. The representative SRS (SR:FA is 10:1) was selected to investigate the compression performance and collapsibility. The preparation and filling method of SRS in the field was proposed, and the effects of gravel, sand, and lime on the mechanical properties of SRS were studied through field tests. The results show that the addition of FA contributed to the strength development of SR, and the addition of lime, sand and rubble have a significant effect on the subgrade bearing capacity of SRS. The subgrade bearing capacity and deformation modulus of SRS in field tests is more than 210 kPa and 34.48 MPa, respectively. The results provide experimental basis and reference for the preparation of SRS, the scientific application of SRS in geotechnical engineering to promote sustainable development.

Antifloating anchors are widely used during the construction of slab foundations to prevent uplift. However, existing methods for calculating the critical length of these anchors have limited capabilities and therefore require further research. As the mechanisms which govern the displacement and stability of antifloating anchors are closely related to those of piles subject to uplift, a simplified anchor model has been developed based on existing concentric thin-walled cylinder shear transfer models used for pile design. Analytical expressions for the critical length of the steel bar and GFRP (glass fiber reinforced polymer) antifloating anchors in rock are derived accordingly before demonstrating the validity of the method through engineering examples. The research results show that when the length of an antifloating anchor is less than a critical length, shear slip failure occurs between the anchor and surrounding material due to excessive shear stress. When the length of an anchor approaches the critical length, the shear stress gradually decreases to the undisturbed state. If the anchor length is larger than the critical length, the uplift loads are safely transferred to the ground without causing failure. The ratio of elastic modulus between the anchor and rock mass was found to be positively correlated with the critical anchoring length. Because the elastic modulus of GFRP bars is lower than that of steel bars, the critical anchoring length of GFRP bars is greater than that of steel bars under the same anchor-to-rock modulus ratio (E_a/E_s). The results show that the proposed calculation method for the critical length of antifloating anchors appears valid and could provide a theoretical basis for the design of antifloating anchors after further refinement.

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.