Experimental and FEM analysis of reduced beam section moment endplate connections under cyclic loading

Intensive research and testing efforts have been underway in order to find better methods of design seismic resistant frames. Reduced beam section (RBS) moment connections have been introduced after the Northridge and Cobe catastrophic earthquake incidents that revealed the lack of connection response in steel frames. Nowadays this type of steel connections is among the most economical and efficient methods in seismic resistant frames application. Although the RBS connection level of both ductile response and reliability is widely investigated using the US design codes and practices, limited data exist from European codes-based research. Recommendations of RBS application in steel frames were prescribed in EC8, Part3. However the reliability of these recommendations is under consideration due to the above mentioned poor existing data. In this paper the results of an experimental study of RBS moment connection with radius cut subjected to cyclic loading and using the HEA profiles – widely used as beam members in Europe – is presented. Two full scale subassemblies with extended endplate bolted beam to column connection– frequently used as moment connection in Europe – were tested and the output results are compared with those obtained from the analytical model using finite element simulation.