A three-year experimental and analytical research program is undertaken to study the design and behavior of steel moment-resisting frames with composites reinforced concrete (RC) infill walls subjected to seismic excitations. The program includes a series of two two-story, one-bay frame experiments, cyclic shear connector experiments, and a comprehensive analytical effort. In the steel frame-RC infill system, the steel beams and columns act as boundary members resisting gavotte loads and axial forces from seismic overturning, while the RC infills serve as webs resisting shear. Simulated seismic load testing of one-third scale, two-story, one-bay frames will be conducted to determine the seismic behavior of steel frame-RC infill composite wall systems. The proportions of strength and stiffness provided to the system by the steel frame and the RC infills will be determined. Fully-restrained (moment) beam-to-column connections partially-restrained will be tested. In addition, cyclic shear tests of connector specimens to quantify the strength of shear studs under cyclic shear and axial tension will also be tested. Data analysis coupled with linear and nonlinear analysis of steel frame-RC infill subassemblages will serve to establish analysis and design recommendations. Experimental observations from the frame tests, coupled with all existing experimental data on similar systems conducted to date which consist mainly of geometry, topology, and constitutive properties of simple computational models for the RC infills (e.g., effective compression struts or membrane elements). This is a project supported under the second year program of research initiative `Composite and Hybrid Structures`, NSF-94-154.
