Wood Shear Wall Performance: Influence of Sheathing Nail Head Geometry
Publication: Practice Periodical on Structural Design and Construction
Volume 14, Issue 4
Abstract
Wood shear wall performance is affected by the materials used for construction including the sheathing fasteners. The model building codes permit different fasteners for sheathing attachment in terms of diameter and length. In general, the nail head geometry is designated in the fastener schedule footnotes by terminology, such as “common,” “sinker,” “casing,” or “finish.” Power-driven nails are collated and the heads are formed to facilitate collation, so the heads may be flat and round with full round geometries or the flat round head may be clipped or notched. The European Yield Limit equations of the National Design Specification assume a smooth round dowel with no head, which leaves the engineering community without a rational basis for specification of head geometry requirements for shear wall construction. To address this issue, three types of nails distinguished by different head geometries were used in shear wall tests to investigate the potential effects of sheathing nail head geometry on shear wall performance. The head geometries were full-round heads (FRH), clipped heads (CLP), and casing heads (CSE), but the nails were otherwise the same. The head-area ratios for these fasteners were 0.83, 0.74, and 0.55 for the FRH, CLP, and CSE nails, respectively. These were used to fabricate shear walls sheathed one side with plywood (height/length ratio=2.0) that were tested using the sequential phase displacement method of fully-reversed cyclic testing. Shear walls with the FRH nails and the CLP nails had the same nominal strength while the CSE nails had a nominal strength that was 78% of the nominal strength of the shear walls with FRH nails. The elastic stiffness’ of shear walls were not statistically different when the source of variation was sheathing-nail head geometry. The test performance was compared to nominal strength calculated from published design values. The walls with FRH and CLP exceeded the expected nominal shear while shear walls with CSE nails underperformed the design value. Nails with FRH and CLP heads cannot be distinguished in performance and are interchangeable for design and construction. Even though CSE nails produce shear walls with the same elastic stiffness, they cause shear capacity to be less than that of walls built with FRH and CLP nails and about 8% less than allowable shear design.
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Acknowledgments
Members of the International Staple, Nail and Tool Association provided the financial support for the testing that is the basis of this publication. The assistance of Wesley Coleman is appreciated.
References
American Forest & Paper Association (AF&PA). (1999). “General dowel equations for calculating lateral connection values.” Technical Rep. No. 12, American Wood Council of the AF&PA, Washington, D.C.
American Forest & Paper Association (AF&PA). (2005). National design specification for wood construction, American Forest & Paper Association, Washington, D.C.
Anderson, E. N., Leichti, R. J., Sutt, E. G., Jr., and Rosowsky, D. V. (2007). “Sheathing nail bending-yield stress: Effect on cyclic performance of wood shear walls.” Wood Fiber Sci., 39(4), 536–547.
Andreason, K. R., and Tissell, J. R. (1994). “Effects of overdriven nails in shear walls.” Rep. No. T94-9, APA—The Engineered Wood Association, Tacoma, Wash.
ASTM. (2005). “Standard test methods for cyclic (reversed) load test for shear resistance of walls for buildings.” ASTM E2126-05, ASTM, West Conshohoken, Pa.
Canadian Standards Association (CSA). (1974). “Wire nails, spikes, and staples (reaffirmed 1998).” B111-1974, Canadian Standards Association, Toronto.
Canadian Standards Association (CSA). (1989). “Engineering design in wood (limit states design).” CAN/CSA-O86.1-M89, Canadian Standards Association, Toronto.
Fonseca, F. S., Judd, J. P., and Burns, J. M. (2006). “Strength of plywood joints with overdriven nails.” For. Prod. J., 56(7/8), 33–38.
Foster, T. (1998). “International Staple, Nail and Tool Association—Nail head test program.” Rep. No. CN8012, Southwest Inspection and Testing, Santa Fe Springs, Calif.
ICC-Evaluation Service (ICC-ES). (2005). “Power-driven staples and nails.” ESR-1539, International Code Council Evaluation Service, Whittier, Calif.
International Code Council (ICC). (2006). International building code, International Code Council, Country Club Hills, Ill.
Langlois, J. D., Gupta, R., and Miller, T. H. (2004). “Effects of reference displacement and damage accumulation in wood shear walls.” J. Struct. Eng., 130(3), 470–479.
Lattin, P. D. (2002). “Fully reversed cyclic loading of wood shear walls fastened with super sheather nails.” MS thesis, Brigham Young Univ., Provo, Utah.
National Research Council of Canada (NRC). (1995). National building code of Canada (1995), 11th Ed., National Research Council of Canada, Ottawa, Canada.
Zacher, E. G., and Gray, R. G. (1985). “Dynamic tests of wood framed shear walls.” Proc., 57th Structural Engineers Association of Southern California Annual Convention, SEAOSC, San Francisco, 41–61.
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© 2009 ASCE.
History
Received: Oct 30, 2008
Accepted: Jan 11, 2009
Published online: Jul 14, 2009
Published in print: Nov 2009
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