Performance of Metal-Plated Wood Joints Exposed to Periods of Soaking Moisture
Publication: Journal of Performance of Constructed Facilities
Volume 26, Issue 6
Abstract
Metal-plated wood truss systems may be rained upon during the construction phase, resulting in the soaking of the connections. In this paper, the results of an investigation of the behavior of metal-plated wood joints subjected to periods of soaking are presented. The wetting regimes included (1) 4-h shower, (2) alternating cycles of a period of shower wetting followed by a period of no shower, and (3) 24-h soaking in a water tank. Results of tests conducted after wetting and after wet-dry cycles were compared with results of dry control tests. The results show the wet joints lost over 40% of their load-carrying capacity in all three wetting regimes. Upon drying, the strength loss was about 10%. Likewise, the stiffness of the joints deteriorated, with stiffness loss ranging from 12 to 37%. In contrast to the load-carrying capacities, there were insignificant recoveries in joint stiffness upon the drying of the specimen, with additional loss of stiffness during the drying process in one of the groups investigated. The results of this study suggest the need to warn against severe wetting or to compensate for this probability of occurrence in truss design standards.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
The authors gratefully acknowledge the laboratory testing assistance provided by Jameel Hanif and Jack Johnson in conducting the experiments.
References
American National Standards Institute/Truss Plate Institute (ANSI/TPI). (1995). “National design standard for metal plate connected wood construction.” ANSI/TPI 1-1995, Truss Plate Institute, Madison, WI.
ASTM. (2007a). “Standard test methods for direct moisture content measurement of wood and wood-base materials.” D4442-07, West Conshohocken, PA.
ASTM. (2007b). “Standard test methods for specific gravity of wood and wood-based materials.” D2395-07, West Conshohocken, PA.
Barksdale, D. (2004). “Disaster recovery response to Tropical Storm Alberto.” Disaster management programs for historic sites, D. H. R. Spennemann and D. W. Look, eds, Association for Preservation Technology, San Francisco, 133–138.
Cramer, S. M., Shrestha, D., and Mtenga, P. V. (1993). “Computation of member forces in metal plate connected wood trusses.” Struct. Eng. Rev., 5(3), 209–218.
Emerson, R. N., and Fridley, K. J. (1996). “Resistance of metal-plate-connected truss joints to dynamic loading.” For. Prod. J., 46(5), 83–90.
Faherty, K. F., Peot nee Kocher, G. L., and Mazza, M. J. (1994). “Metal truss plates: Less than full-depth penetration and shear buckling.” Proc., Structures Congress XII, ASCE, New York, 695–700.
Foschi, R. O. (1977). “Analysis of wood diaphragms and trusses. Part II: Truss-plate connections.” Can. J. Civ. Eng., 4(3), 353–362.
Groom, L. H. (1994). “Effect of moisture cycling on truss-plate joint behavior.” For. Prod. J., 44(1), 21–29.
Groom, L., and Polensek, A. (1992). “Nonlinear modeling of truss-plate joints.” J. Struct. Eng., 118(9), 2514–2531.
Gupta, R., Gebremedhin, K. G., and Grigoriu, M. D. (1992). “Characterizing the strength of wood truss joints.” Trans. ASAE, 35(4), 1285–1290.
McAlister, R. H. (1989). “Interaction between truss plate design and type of truss framing.” For. Prod. J., 39(7-8), 17–24.
McAlister, R. H. (1990). “Tensile loading characteristics of truss plate joints after weathering and accelerated aging.” For. Prod. J., 40(2), 9–15.
McCarthy, M., and Wolfe, R. W. (1987). “Assessment of truss plate performance model applied to southern pine truss joints.” Research Paper FPL-RP-483, U.S. Department of Agriculture, Forest Products Laboratory, Madison, WI.
Meeks, J. E. (1996). “If I had not seen it, I would not have believed it!.” Pract. Period. Struct. Des. Constr., 1(4), 119–121.
Mtenga, P. V., Cramer, S. M., Peyrot, A. H., and Wolfe, R. W. (1995). “System factors for light-frame wood truss assemblies.” J. Struct. Eng., 121(2), 290–300.
Shrestha, D., and Albani, T. (1996). “Out-of-plane capacity of truss connector plates.” For. Prod. J., 46(2), 79–81.
Information & Authors
Information
Published In
Copyright
© 2012 American Society of Civil Engineers.
History
Received: Apr 1, 2011
Accepted: Aug 1, 2011
Published online: Aug 3, 2011
Published in print: Dec 1, 2012
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.