Seismic Performance of Wall-Type Concrete-Filled Steel Tubular Column to H-Beam Connections with Internal Diaphragms

Abstract

This study introduces a new internal diaphragm joint to connect steel beams with wall-type concrete-filled steel tubular (WCFST) columns. This study combines experimental research with numerical simulations for analysis. Firstly, one full-scale test specimen was designed and subjected to cyclic loading. The obtained failure mode and hysteresis curves illustrate that the joint specimens exhibit ample energy dissipation capacities. Subsequently, a reliable FE model was obtained based on experimental verification, and parametric analysis was conducted. The findings indicate that axial compression ratios critically affect the load-carrying capacity and displacement at failure, with a 2% reduction in capacity for each 0.1 increment in the ratio. The thicknesses of the column web and flange in the joint area are recommended to be 0.85 to 1.2 times and 1 to 1.2 times the beam flange thickness, respectively. The length of the internal diaphragm is advised to be between 0.2 and 0.3 times the width of the cross-section. Overall, these results significantly enrich our understanding of WCFST systems and will inform future design and construction best practices.