Seismic Behaviour of RWS Moment Connections to Deep Columns with European Sections

The design of reduced web section (RWS) connections is becoming more often, while the research is focusing on both areas: (a) the performance of beams with large web opening areas near the supports, and (b) the seismic behaviours of steel beam-to-column connections of different types when subjected to cyclic loads. The beam web opening is used as a mechanism to counterbalance the low inelastic capacity of the welds and to shift the stresses from the welding and shear panel zones to the weak beam section in line with the concept of “weak beam-strong column” often employed for the seismic-resistant design of Moment Resisting Frames (MRFs). However, limited data yet exists on the design and seismic behaviour of such connections and those are only for UKB and UKC section profiles. This paper presents an extensive FE study of the seismic performance of fully welded RWS moment connections to deep columns. The effect of using different beam spans is also investigated together with the effect of web opening size and position (web opening at different shear-moment interactions). European HE and IPE profiles are employed for this study in an effort to introduce RWS connections in Eurocode 8, and understand potential variations in design when using European sections as previously reported in RBS connections. Finally, a step-by-step design procedure is presented based on AISC 358 (AISC 358 [3]).