Investigating the behavior of innovative hybrid connection of reinforced concrete beam to cruciform steel column using two web plates

Load transfer from beam to column in connections by a reliable path is one of the most important and critical issues that has been proposed and studied in various details by many researchers. The failure of the connection between the column and the beam is one of the main reasons that causes the failure and accelerates the collapse process of the structures. In the current research, it has been tried to increase the capacity and strength of the connection by proposing an innovative hybrid connection of reinforced concrete beam to steel column in two cases and provide the possibility of using these details in heavier sections. The innovative connection is proposed in two ways: 1- placing two steel shear web plates inside the concrete beam and connecting it with the end plate to the steel column 2- placing two steel shear web plates with upper and lower flange plates together inside the concrete beam and its connection with the end plate to the steel column. In this regard, after modeling and validating the prototype, the capacity and behavior of the proposed connections have been checked in Abaqus finite element software. The results of the analysis show that an increase in energy absorption with the addition of continues plate, and this effect is more visible with the increase in the dimensions of the beam and column in higher drifts. Also, the addition of flange plates to the steel part of the hybrid concrete beam is very effective in the overall ductility of the connection, and this has caused a 24% increase in the ductility coefficient and 13% in the maximum strength compared to the other proposed connections. At the same time, increasing the length of the steel part of the beam has increased the strength of the connection in all cases.