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Through both test and numerical simulation methods, the tensile performance of steel tube concrete columns joint connected by Thread-fixed One-side Bolt (TOB) was examined and contrasted with those connected by Traditional High-strength Bolts (THB). It was found that the failure mode of TOB joints is decided by the dimension of the joint including the column wall thickness. When the column wall thickness is small, the TOB joints may fail due to excessive deformation of the steel tube wall, causing the TOB to be pulled out. Filling the steel tube with concrete significantly enhances the ultimate load and stiffness of the TOB joint, though its influence on the yielding load is minimal. Increasing the depth of bolt anchorage in concrete can marginally improve the ultimate load capacity of the joint. Compared to THB joints with same dimension, TOB joints offer a comparable yielding load capacity but with a notably lower ultimate load capacity. Following the test and numerical analysis, equations for calculating the yielding load of TOB joints were proposed. The comparison between the calculated results and simulation results showed that the proposed equations can accurately predict the yielding load of the joint. The Thread-fixed One-side Bolt (TOB) does not require a nut and is directly anchored in a threaded bolt hole, making it possible to complete the installation from one side only. This is particularly advantageous for connecting closed-section components, such as steel tube columns. Through both test and numerical simulation methods, the tensile performance of steel tube concrete columns joint connected by TOB was examined and contrasted with those connected by Traditional High-strength Bolts (THB). It was found that the failure mode of TOB joints is decided by the dimension of the joint including the column wall thickness. When the column wall thickness is small, the TOB joints may fail due to excessive deformation of the steel tube wall, causing the TOB to be pulled out. Filling the steel tube with concrete significantly enhances the ultimate load and stiffness of the TOB joint, though its influence on the yielding load is minimal. Increasing the depth of bolt anchorage in concrete can marginally improve the ultimate load capacity of the joint. Compared to THB joints with same dimension, TOB joints offer a comparable yielding load capacity but with a notably lower ultimate load capacity. Following the test and numerical analysis, equations for calculating the yielding load of TOB joints was proposed. The comparison between the calculated results and simulation results showed that the proposed equations can accurately predict the yielding load of the joint. [Display omitted] • Tests on TOB (Thread-fixed One-side Bolt) bolted CFST column connection were conducted. • FE model was established, and analysis on the behavior of TOB connections was made. • Comparison between the TOB and THB (Traditional High-strength Bolt) was made. • Equations for calculating the yielding load of TOB connection was established. [ABSTRACT FROM AUTHOR]

The One-side bolts are widely used in the connection of the closed section members in the prefabricated buildings. As a novel type of one-side bolt, T-head Square-neck One-side Bolt has the advantages of the simple structure, the convenient installation, and no need for special installation tools. In this paper, the sub-model for the tension region of the T-stub bolted beam-column connection was selected as the research object, and the cyclic test was conducted on four T-head Square-neck One-side Bolted Connections (TSOBCs) for T-stub to Hollow Section Steel Column (HSSC) and two Traditional High-strength Bolted Connections (THBCs) for comparison. The results of the test including the failure modes, the applied force-displacement hysteretic curves, the applied force-displacement envelope curves, the deformation capacity and ductility, the strength degradation, the stiffness degradation, the energy dissipation, and the strain evolution are discussed and analyzed in this paper. The experimental results denote that: (1) There are two failure modes in the test, mode i, HSSC wall yielding and mode ii, T-stub flange yielding; (2) The initial stiffness and peak bearing capacity of the TSOBCs decreased by 2.5% ~ 35.6% and 21.7% ~ 39.4%, respectively, compared with those of the THBCs; (3) When the failure mode ii occurred, the ductility and the equivalent damping coefficient of the TSOBC with vertical mounting holes are 42.5% and 5.4% higher than those of the THBC, respectively. Besides, the plastic deformation, rigid displacement, and bolt offset in the TSOBCs are analyzed using finite element models. [Display omitted] • A novel T-head Square-neck One-side Bolted Connection (TSOBC) was proposed. • Test on TSOBC of T-stub to hollow section column under cyclic load was conducted. • Cyclic performances of TSOBC were compared with traditional bolted connection. • Vertical mounting hole improves the ductility and energy dissipation of TSOBC. [ABSTRACT FROM AUTHOR]