Effects Of Rib Plates And Haunch On The Behavior Welded Prequalified Moment Connections Under Cyclic Loading

One of the connections that are less use by designers due to the difficult implementation is welded unreinforced flange welded web connection. Almost can be said that this type of connection can be use without design. Studies on this connections indicated presence of plastic strains in near the beam to column connection causes decreased levels of confidence this connections. In this article studied on I shape beam to column moment connections with welded unreinforced flange-welded web (WUF-W), welded top and bottom flange plate (WFP) and reduced beam section (RBS). For this propose for each specimen design connection with ST37 material properties according to Iranian national Cone No-10 (Design Steel Structures specifications). With the Abaqus finite element analysis software studied and compares hysteresis curves and performance of each connection under cyclic loading. Finally recommended details for Increase safety level of WUF-W moment connection. This study has shown that energy dissipate of WFP 20 and 52 present respectively was more than WUF-W and RBS moment connection. Load capacity of WFP 19 and 54 present respectively was more than WUF-W and RBS moment connection. Reinforce WUF-W with haunch had best results in energy dissipate, rigidity and load capacity that increase respectively 10.5, 18.5 and 8 present parameters.