Research on seismic performance of a novel SS-CFSST column to H-beam connection

• Published in: Journal of constructional steel research Vol. 215; p. 108549
• Main Authors: Wang, Zhen, Feng, Shuaike, Zhou, Xuejun, Wen, Tingting, Liu, Zhe, Zhang, Qi
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.04.2024
• Subjects: Column-to-beam connection; Load-bearing capacity; Numerical analysis; Parametric analysis; Seismic performance; Numerical analysis; Load-bearing capacity; Parametric analysis; Column-to-beam connection; Seismic performance
• ISSN: 0143-974X; 1873-5983
• DOI: 10.1016/j.jcsr.2024.108549

Special-shaped concrete-filled square steel tube (SS-CFSST) columns are a type of prefabricated steel house structural form. They retain the characteristic high load-bearing capacity of the steel and concrete composite structures without protruding from the wall. This paper proposes a new type of connection form by improving the SS-CFSST column-steel beam outer sleeve connection. Cyclic loads were applied to nine specimens differing in terms of steel hoop width, side plate width, side plate length, and overall thickness. The failure modes, hysteresis curves, strength and rigidity degradation, and energy dissipation capacity are analysed in this study. The failure modes include side-plate fracture, beam-flange tear, and beam-plastic hinges. The hysteresis curves exhibit shuttle shapes without pinching. The equivalent viscous damping coefficients of the samples range from 0.16 to 0.26. Based on these results, a finite element model is established, and its accuracy is verified according to a comparison with the test results. A parameter analysis is also described herein. The results indicate that the key factors influencing the load-bearing capacity of these connections include (i) the thickness and height of the steel hoop and the side plate, (ii) the steel tube's width-to-thickness ratio, and (iii) the steel's yield strength. Specifically, the ratio of the height of the side plate on the beam flange's outer (hw) to inner (hn) dimension should not exceed 1.5. Moreover, the load-bearing capacity and stiffness of the connections are not affected when the axial compression ratio (n) is in the range of 0–0.6. •A novel special-shaped concrete-filled square steel tube (SS-CFSST) column to H-beam connection was proposed.•The seismic performance of the new connection was investigated based on nine specimens with different design parameters.•A parameter analysis was conducted on the factors affecting the bearing capacity of the connection.