Parametric analysis of the cyclic behavior of a new T-shaped flexural connection of steel beams to concrete filled tubular (CFT) columns

T-shaped joints are one type of beam-column connections in steel structures. Ease of construction, transportation, and installation, as well as suitable ductility, economy, and durability, are the advantages of this type of connection. However, bolting of the T-shaped flange to tubular columns is very challenging due to limited access. In this research, by using through bolts for connecting the T-shaped flanges and the column, the transfer of forces and the rigidity of the panel zone have been provided. This is especially effective in concrete filled tubular (CFT) columns where the passage of concrete through the panel zone is important. On the other hand, the direct transfer of stresses to the column, the stretch of through bolts under cyclic loads, which reduces their performance level, as well as accumulation of bolts, which is caused by large diameter, and four-way connection, especially at a long opening that interferes with the passage of concrete through the panel zone are controversial. Therefore, to provide a suitable solution, in an innovative action, the external diaphragm of the column with through bolts was used simultaneously and the performance of the connection was examined.
In this study, using ABAQUS software, one connection sample with a through bolt and another with an external diaphragm were investigated. The results show that the overall performance of both kinds of connection is quite good.