Experimental and Numerical Investigation of Innovative Steel Beam–Column Welded Connection with Reduced Web Opening under Cyclic Loading

Steel beam column welded connection fails in steel moment resisting frame construction under earthquake strain. In this case, the analysis was performed with a steel web opening beam column welded connection and experimental verification. For the investigation, an innovative type of web opening with double elliptic shape, double triangle shape, square and triangle, circular and elliptic shape was proposed. The study examined 13 connections, including one basic connection and 12 connections with opening and stiffening plates. A novel type of connection with a stiffening plate has also been proposed. In this regard, reinforcing plates have been added to the suggested opening shapes. The triangle and square shapes have fillet radios to lessen the stress concentration impact at the corners. The plane beam column welded connection has been tested and verified using FEM analysis under cyclic and monotonic loading. The experimental results are consistent with the simulated data. A cyclic study revealed that the aperture with the elliptic connection and stiffening plate has the highest moment bearing capacity. The square opening connection with no stiffening plate has the maximum energy dissipation of all. The PEEQ index for all connections has also been investigated. Out of plane displacement has also been compared for all shapes. About 20% difference in moment carrying capacity can be found between the lowest connection type RWC-SO to highest capacity connections RWC-DESO. The least amount of strength degradation can be found in RWC-CO type which is three times less than RWC-ESO type of connection.