Triaxial Load Testing of Metal and FRP Roof-to-Wall Connectors
Publication: Journal of Architectural Engineering
Volume 17, Issue 3
Abstract
The allowable capacity of conventional roof-to-wall metal connectors is based on results of unidirectional component tests that do not simulate triaxial aerodynamic loading effects induced by high-wind events. The results of wind and wind-driven rain tests conducted at a full-scale facility were used to create a database on aerodynamic and aerohydrodynamic load effects on roof-to-wall connectors. Based on these results, three axial mean force components (triaxial mean loads) were combined into a series of resultant mean force vectors. A new test protocol was then developed for roof-to-wall connectors under simulated triaxial loading as opposed to simple uniaxial loading. The findings confirm that current testing methods tend to overestimate the actual load capacities of metal connectors. The performance of a nonintrusive roof-to-wall connector system using fiber-reinforced polymer (FRP) ties was also tested and compared with that of a traditional metal connector under simulated aerodynamic loads. The test results demonstrated the validity of FRP ties as an alternative to hurricane clips for use in timber roof-to-wall connection systems.
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Acknowledgments
This research was supported by the National Science Foundation. Additional support was provided by the Gulf of Mexico Regional Sea Grant Program, Florida Center of Excellence in Hurricane Damage Mitigation and Product Development, and Soprema, Inc., of Wadsworth, Ohio. The WoW component of the project was additionally supported by the Florida Sea Grant College Program. The six-fan WoW was sponsored by RenaissanceRe Holdings, Ltd., of Hamilton, Bermuda. The authors wish to thank Dr. Emil Simiu for his input toward the development of this study and graduate students Sheik Saad Ahmed, Piyush Kawade, Edgar Polo, Cetin Canbek, and Brandon Mintz for their assistance in the experiments.
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© 2011 American Society of Civil Engineers.
History
Received: Jul 16, 2010
Accepted: Jan 20, 2011
Published online: Jan 22, 2011
Published in print: Sep 1, 2011
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