Study on the moment capacity of a connection joining an I-beam to concrete-filled multicellular steel tube walls

Abstract

Recently, concrete-filled multicellular steel tube (CF-MCST) walls are being widely used in China. This paper presents a theoretical and numerical study on the moment capacity of a beam-to-wall connection in which an endplate and two side-plates grip the wall-end by welding, and then the beam is connected to the endplate by the welded flanges and the bolted web. Finite element (FE) analysis is conducted, and its accuracy is validated by comparing the analysis results with experimental results in literature. A parametric study of the connection is conducted to gain insight into the mechanical behavior of the connection. Yield line analysis is used to derive equations predicting the moment capacity. Comparison between the analyses shows good agreement between the predicted capacities and the FE analysis results. The error rate was less than 10%. The minimum required thickness of the endplate is derived for developing the full moment strength of the beam. A minimum endplate total length (1.42b + hb) is obtained and verified to ensure the full strength development of the beam when the endplate thickness is the minimum value. Finally, design recommendations are proposed.