Civil Engineering Study 95-3
PREFACE To aid in adapting cold-formed steel to the residential market, a research project was initiated in 1993 at the University of Missouri-Rolla. Design issues relating to the use of cold-formed steel members and connections in residential roof truss systems were the focus of the project. The purpose of this research was to study the behavior of cold-formed steel roof truss systems and to establish appropriate design recommendations. Overall, the research findings were intended to aid the promotion of cold-formed steel as a safe, serviceable, and cost effective alternative in residential construction. The project consisted of a review of available literature, followed by a comparative analysis of experimental truss behavior to a computer generated model. An in-depth review of research reports and publications yielded minimal information, however design issues were discussed with interested design engineers and truss manufacturers regarding the state-of-the-art. The experimental investigation involved an evaluation of the overall truss behavior using full-scale truss assemblies. Based on this information, a computer generated model was created to simulate the truss assembly. An evaluation of deflection and stress data was used to correlate the computer model to the full-scale truss. The computer model and AISI Specification formed the basis used to establish the predicted failure load, which was then compared to the tested failure of the full-scale truss assembly. The conclusions obtained from the experimental investigation were used to create design recommendations. The recommendations prescribe minimum strength and serviceability requirements for trusses fabricated using cold-formed C-sections and self-drilling screws. The design recommendations are intended to compliment the AISI Specification. This report is based on the thesis presented to the Faculty of the Graduate School of the University of Missouri-Rolla in partial fulfillment of the requirements for the degree of Masters of Science in Civil Engineering. This investigation was sponsored by the National Science Foundation and the American Iron and Steel Institute. The technical guidance provided by the Technological Research Subcommittee of the AISI Residential Advisory Committee and Steve Walker (chairnan) is gratefully acknowledged. Thanks are also extended to A. Ziolkowski and R. B. Haws, AISI staff, and J. B. Scalzi of the National Science Foundation.
Civil, Architectural and Environmental Engineering
American Iron and Steel Institute
National Science Foundation (U.S.)
Wei-Wen Yu Center for Cold-Formed Steel Structures
Cold-Formed Steel Series
Missouri University of Science and Technology
01 May 1995
© 1995 Missouri University of Science and Technology, All rights reserved.
Harper, Michael M.; LaBoube, Roger A.; and Yu, Wei-wen, "Behavior of cold-formed steel roof trusses" (1995). CCFSS Library (1939 - present). 47.