Mechanical performance and failure mode judgment criteria of grouted sleeve connectors considering large deformation and grouting compactness

Three groups of 36 grouted sleeve connectors (GSCs) with different grouting compactness were experimentally investigated under monotonic tension and large-deformation reciprocating tension-compression. The experimental results showed that the failure mode contained the tensile fracture of the steel bar (Failure Mode I) and bond-slip failure (Failure Mode II). The yield strength, ultimate strength, and elongation of GSCs gradually decreased, while the residual deformation increased as the grouting compactness decreased. The average ultimate strength of GSCs with 90 % grouting compactness was 561.61 MPa, a 124.46 % enhancement over that of GSCs with 60 % grouting compactness. The loading method mainly affected the residual deformation of GSCs, which increased with the cycle number of large-deformation reciprocating loadings at consistent grouting compactness. Subsequently, based on the effects of the grouting compactness and large deformation on the mechanical performance of GSCs, this study combined the critical grouting compactness and f u / f sy to judge the failure mode of GSCs with steel bar diameters of 20 cm, which were determined to be 90 % and 1.4, respectively. These findings provide a foundation for designing assembled structural connections and ensuring the safety of assembled structures. • Novel double-control method proposed for grouting compactness simulation. • Discussed effects of grouting compactness and loading conditions. • Confirmed critical grouting compactness and f u / f sy . • Criteria considering large deformation proposed for failure mode judgment of GSCs.