SEISMIC BEHAVIOR OF RCS BEAM-COLUMN-SLABSUBASSEMBLIES DESIGNED FOLLOWING A CONNECTIONDEFORMATION-BASED CAPACITY DESIGN APPROACH

摘要

This paper presents test results for four RCS subassemblies consisting of Reinforced Concrete (RC)rncolumns and composite Steel (S) beams with reinforced concrete slab, under displacement reversals. Thernspecimens were designed following a strong column-weak beam criterion, with the connection regionsrndesigned using a deformation-based capacity design procedure to limit joint deformations and damage.rnTwo simple RCS joint details, consisting of either overlapping U-shaped stirrups passing through the steelrnbeam web or steel band plates wrapping around the RC column just above and below the steel beamrnflanges were used to provide joint confinement. The performance of the specimens was evaluated in termsrnof lateral load vs. story drift response, beam and joint deformations, energy dissipation capacity, and storyrndrift contributions from different structural components. Test results indicated satisfactory seismicrnperformance of RCS subassemblies under large lateral displacement reversals. To evaluate the effect ofrnjoint deformations on RCS system behavior, dynamic analyses of a six-story RCS frame system underrnvarious ground motion records were conducted. In one of the three RCS moment-resisting framesrnanalyzed, the composite joint regions were modeled as rigid joint panels. In the other two frames, the jointrnregions were modeled as flexible joint panels designed following a deformation-based design approach,rnwhich would limit the maximum joint shear deformations to approximately 1.2% and 0.5%. Results fromrninelastic dynamic analyses show that joint deformations may have a significant effect on maximum storyrndrift, and thus joint flexibility shall not be neglected in analysis of RCS frames. In addition, different jointrndesign philosophies may affect the inelastic deformation demand imposed on beams and columns.