Seismic Behavior of Steel Buildings with Combined Rigid and Semi-Rigid Frames

Authors : Bülent AKBAŞ

Pages : 253-264

View : 15 | Download : 8

Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :The 1994 Northridge Earthquake insert ignore into journalissuearticles values(USA); has shown the vulnerability of welded moment connections in steel moment resisting frames insert ignore into journalissuearticles values(MRFs); subject to severe earthquake ground motions insert ignore into journalissuearticles values(EQGMs);. Since then, as an alternative connection type, bolted connections, often called semi-rigid connections, are considered for the retrofit and new design of steel MRFs in high seismicity regions. This paper investigates the seismic design and performance of a hybrid system, consisting of welded moment frames and bolted semi-rigid frames. For this purpose, an analytical study is carried out on two steel buildings with interior semi-rigid steel frames having beam-to-column connections with different strength and stiffness ratios. The two buildings, of 5 and 10 stories, are designed in compliance with the current seismic design codes for two different cases. In the first case insert ignore into journalissuearticles values(Case 1);, the interior frames are assumed to be simply connected. In the second case insert ignore into journalissuearticles values(Case 2);, the interior frames are assumed to be semi-rigidly connected. The buildings are subjected to three representative earthquakes. The evaluation of the results indicates that making the interior frames semi-rigid can lead to less story shear and lower column and connection moments and will increase the lateral load capacity of the building.
Keywords : Semi rigid steel frames, Welded connections, Bolted connections, Non linear dynamic time history analysis, Seismic behavior, Connection rigidity