Experimental Investigation of Cyclic Behavior of Reformed Rigid Steel Beam-double Column Connections

Beam-column connection is one of the most important parts of steel ductile flexural frames, as the performance of frame is depending on connection’s flexibility. The rigid steel connections with cover plate are one of the most common connections in Iran. Due to the importance of seismic resistant design, it is necessary to investigate their seismic performance. In this experimental research, three steel connection specimens with 1/2 scale with introduction of new T-shape plate were built based on Iran steel code to evaluate their seismic performance and the specimens were subjected to cyclic loading. The results indicated that specimen designed based on Iran steel code cannot satisfy all of rigid connection criteria, and also, the strength was increased up to 10% and ductility was decreased up to 18% by adding the plates. Plastic hinges were transmitted to flange of beams, and the collapse mechanism of connections were changed due to deleting groove welding, strength and ductility were decreased respectively.