ABSTRACT
Several configuration details of both joint typologies were examined before choosing the most suitable one. Two types of rib-reinforced steel moment connections were observed: with single and dual rib, Figure 2a, b. Results from FEM analysis show that there is no significant difference neither in global nor in local response of the joint using single and dual rib type configuration. Comparison of local response showed that dual rib configuration is slightly more efficient to prevent penetration of yielding and flange local buckling beyond the
1 INTRODUCTION
The study deals with the response of steel moment-resisting connections reinforced with flat steel plates. Two types of plate-reinforced connections are studied: welded cover-plate (CP) beam-to-column joint which comprises additional rectangular plate attached on the top and bottom flanges of the beam, Figure 1a, b, and welded rib-stiffened (RS) beam-to-column joint where single triangular rib is used on the top and bottom flanges of the beam, Figure 1c, d. The design objective for the welded RS and CP connections, based on the capacity design concept, is to relocate inelastic action away from the face of the beam-to-column connection, thus reducing the possibility of brittle failure conditions. Beside two joint types and two different combinations of material (S460/S690 steel column and S355 steel beam), other parameters of the study are: different loading histories (monotonic and cyclic) and the level of axial force in the column, which may be important especially in braced frames. Especially the last parameter is still not well investigated. Moreover, hybrid-steel approach represents an innovation in seismic design in Europe and the actual seismic design rules do not cover this specific configuration.
