This paper presents an experimental study of the cyclic behavior of a composite structural system consisting of partially-restrained (PR) steel frames with reinforced concrete infill walls. The composite interaction is achieved through the use of the headed stud connectors along the steel frame-infill interfaces so that the two main components of the system share in the resistance of lateral shear and overturning moment. Having the relatively light steel frame constructed using PR connections maximizes the economy of the system, while still ensuring system integrity in the post-peak range of deformation. The one-bay, two-story test specimen was built at one-third scale. The study shows that this system has the potential to offer strength appropriate for resisting the forces from earthquakes and stiffness adequate for controlling drift for low- to moderate-rise buildings located in earthquake-prone regions. Redundancy is also exhibited in this system through alternate load paths occurring at different levels of loading, including shear stud-infill interaction, steel frame-infill strut interaction, and deformation of the steel frame. Improvement is needed for reducing the post-peak strength degradation observed in the present study.
Bibliographical noteFunding Information:
Funding for this research was provided by the National Science Foundation (NSF) (Grant No. CMS-9632506) under Dr. Shih-Chi Liu as part of the U.S.–Japan Cooperative Research Program, Phase 5 on Composite and Hybrid Structures (CHS), and by the University of Minnesota. In-kind funding and materials were provided by LeJeune Steel Company, Minneapolis, MN. The authors gratefully acknowledge this support. The authors would like to thank Mr. L.A. Wyllie, Degenkolb Engineers, Dr. V. Mujamdar, National Science Foundation, Dr. S.A. Mahin, University of California at Berkeley, and the other members of the Hybrid Wall Systems coordination group of the NSF CHS program for providing advise throughout this research project. The authors would also like to thank Mr. P.M. Bergson, University of Minnesota, Mr. L.A. Kloiber, LeJeune Steel Co., Minneapolis, MN, and Dr. K. Nozaka, Ritsumeikan University, Kusatsu, Shiga, Japan, for their assistance in conducting this research. Any opinions, findings, or conclusions and recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation.
- Composite wall
- Infill wall
- Partially-restrained connection
- Steel frame