Influence of Sheathing Gaps on Wood Floor Systems


  • Rafik Y. Itani


Beams, composite structures, construction materials, deflection, deformation, fasteners, floors, joists, loads (forces), mechanics, moments, plywood, stresses


This paper describes a comparative study of the partial composite action of wood floors with and without sheathing gaps. The beams investigated consist of plywood sheathing bonded to joists with elastomeric adhesive. Beams are considered to be simply supported and subjected to uniformly distributed loading. Results for continuous sheathing, open gaps at third and fourth points are compared and displayed graphically.

It is shown that the influence of gaps on the partial composite action is drastic and can increase deflections by as much as 82%, compared to a system with continuous sheathing. Little difference is obtained when comparing a beam with gaps at third and fourth points.


Anderson, M. A. 1975. Behavior of wood beams with an elastomeric adhesive. M.S. thesis, Washington State University, Pullman. WA.nBessette, A. 1977. An evaluation of elastomeric adhesive bonded design theory and the effect of panel gaps in T-beams. M.S. thesis, Washington State University, Pullman, WA.nBrito, F. 1977. Investigation of the elastomeric adhesive bonded wood T-beam having gaps in the flange. M.S. Thesis, Washington State University, Pullman, WA.nGillespie, R. H. 1972. Elastomeric adhesives in building construction. Building Research, Oct./Dec.nGoodman, J. R. 1967. Layered wood systems with interlayer slip. Ph.D. thesis. University of California, Berkeley. CA.nGoodman, J. R. 1969. Layered systems with interlayer slip. Wood Sci.1(3):148-158.nGoodman, J. R., and E. P. Popov 1968. Layered beam systems with interlayer slip. Struct. Div., ASCE Proc. Paper 6214, 94(ST11):2535-2547.nGoodman, J. R., et al. 1974. Composite and two-way action in wood joist floor systems. Wood Sci.7(1):25-33.nGranholm, H. 1949. Om sammansatta balkar och pelare med sarskild hansyn till spikade trakonstruktioner (On composite beams and columns with particular regard to nailed timber structures). Chalmers Tekniska Hogskolas Handlingar, No. 88.nHoyle, R. J., Jr. 1972. Wood technology in the design of structures, 2nd ed. Washington State University, Pullman, WA.nHoyle, R. J., Jr. 1973. Behavior of wood I-beams bonded with elastomeric adhesive. College of Engineering, Research Division Bulletin 328, Washington State University, Pullman, WA.nHoyle, R. J., Jr. 1976. Designing wood structures bonded with elastomeric adhesives. For. Prod. J.26(3): 28-34.nHoyle, R. J., Jr. and M. A. Anderson. 1975. Performance predictions for elastomeric adhesive bonded wood structural systems. College of Engineering, Research Report 75/57-2, Washington State University, Pullman. WA.nItani, R. Y., and F. A. Brito. 1978. Elastomeric bonded wood beams with transverse gaps. J. Str. Div. ASCE Proc. Paper 14095, 104(ST10):1595-1609.nKuenzi, E. W., and T. L. Wilkinson. 1971. Composite beams—effect of adhesive on fastener-rigidity. USDA Forest Service Research Paper FPL-152.nMcCutcheon. W. J. 1977. Method for predicting the stiffness of wood-joist floor systems with partial composite action. USDA Research Paper FPL-289.nMcGee, D. W., and R. J. Hoyle, Jr. 1974. Design method for elastomeric adhesive bonded wood joist deck systems. Wood Fiber6(2):144-155.nNewmark, N. M., C. P. Sliss, and I. M. Veist. 1951. Tests and analyses of composite beams with incomplete interaction. Proceedings, Society for Stress Analysis19(1).nPleshkov, P. F. 1952. Teoriia rascheta depeviannykh (Theoretical studies of composite wood structures). Moscow, USSR.nRose, J. D. 1969. Field glued plywood floor test. American Plywood Association Laboratory, Report 118.nSazinski, R. J., and M. D. Vanderbilt. 1979. Behavior and design of wood joist floors. Wood Sci.11(4):209-220.nThompson, E. G., J. R. Goodman, and M. D. Vanderbilt. 1975. Finite element analysis of wood layered systems. ASCE101(ST12):2659-2672.nTremblay, G. A., J. R. Goodman, and M. E. Criswell. 1976. Non-linear analysis of layered T-beams with interlayer slip. Wood Sci.9(1):21-30.nVanderbilt, M. D., J. R. Goodman, and M. E. Criswell. 1974. Service and over-load behavior of wood joist floors systems. ASCE Proc. Paper 10274, 100(ST1):11-29.nVick, C. B. 1971. Elastomeric adhesives for field gluing plywood floors. Prod. J.21(8):34-42.n






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