A Review Of Creep In Wood: Concepts Relevant To Develop Long-Term Behavior Predictions For Wood Structures

Authors

  • Siegfried M. Holzer
  • Joseph R. Loferski
  • David A. Dillard

Keywords:

Creep, creep models, time-dependent modeling, creep buckling, finite element, long-term predictions

Abstract

A review is presented of the effects of constant and transient moisture and temperature conditions on the time-dependent behavior of wood as a material and as a structural element. A rational approach towards the identification of long-term behavior of wooden structures is proposed. Utilizing the fact that wood is a combination of several polymers, polymer viscoelasticity concepts are suggested to enhance the predictive capabilities. A finite element procedure is outlined to indicate how design predictions can be made. Some attention is given to structures such as domes where creep of the wood could lead to structural instabilities.

References

American Institute Of Timber Construction. 1985. Timber construction manual, 3rd ed. John Wiley & Sons, Inc., New York.nArima, T. 1972. Creep in process of temperature changes: I. Creep in process of constant, elevated, and decreased temperature. J. Jap. Res. Soc. 18(7):349-353.nArmstrong, L. D., and G. N. Christensen. 1961. Influence of moisture changes on deformation of wood under stress. Nature 191:869-870.nArmstrong, L. D., G. N. Christensen, and R. S. T. Kingston. 1960. Effect of moisture changes on creep in wood. Nature 185: 862-863.nBach, L. 1965. Nonlinear mechanical behavior of wood in longitudinal tension. Ph.D. thesis, Syracuse University.nBach, L, and R. E. Pentoney. 1968. Nonlinear mechanical behavior of wood. For. Prof. J. 18(3): 60-66.nBarrett, J. D. 1982. Effects of loading time on design. Pages 301-316 in R. W. Meyer and R. M. Kellog, eds. Structural uses of wood in adverse environments. Society of Wood Science and Technology, Van Nostrand Reinhold Company, New York.nBazant, Z. P. 1985. Constitutive equation of wood at variable humidity and temperature. Wood Sci. Technol. 19:159-177.nBhatnagar, N. S. 1964. Creep of wood in tension parallel to grain. Holz Roh- Werks. 22(8):296-299.nBodig, J. 1982. Moisture effects on structural use of wood. Pages 53-75 in R. W. Meyer and R. M. Kellog, eds. Structural uses of wood in adverse environments. Society of Wood Science and Technology. Van Nostrand Reinhold Company, New York.nBodig, J, and B. A. Jayne. 1982. Mechanics of wood and wood composites. Van Nostrand Reinhold, New York.nBoyle, J. T., and J. Spence. 1983. Stress analysis for creep. Butterworths, London.nBrock, G. 1968. The behavior of nailed joints under wood and short duration loading. Proceedings CIB TRADA International Symposium on Joints in Timber Structures. Hughenden Valley, TRADA, London, 1965.nBushnell, D. 1977. A strategy for the solution of problems involving large deflections, plasticity, and creep. Int. J. Num. Meth. Engng. 11:683-708.nCaulfield, D. F. 1985. A chemical kinetics approach to the duration-of-load problem in wood. Wood Fiber Sci. 17(4):504-521.nChan, E. C. Y. 1983. Nonlinear geometric, material, and time dependent analysis of reinforced concrete shells with edge beams. Ph.D. dissertation, University of California, Berkeley.nClauser, W. S. 1959. Creep of small wood beams under constant bending load. For. Prod. Lab. Forest Service U.S.D.A. Report No. 2150.nDavidson, R. W. 1962. The influence of temperature on creep in wood. For. Prod. J. 12(8):377-381.nDillard, D. A., K. C. Gramoll, and H. F. Brinson. 1989. The implications of the fiber truss concept for creep properties of laminated composites. Composite Structures (in press).nDillard, D. A., and C. Hiel. 1985. Singularity problems of the power law for modeling creep compliance. Pages 142-148 in Proceedings of the 1985 SEM Spring Conference on Experimental Mechanics. Society for Experimental Mechanics, Las Vegas.nFeldborg, T., and M. Johansen. 1987. Slip in joints under long-term loading. CIB TRADA International Council for Building Research Studies and Documentation. Timber Structures W18A. Dublin, Ireland. Meeting twenty. September.nFerry, J. D. 1980. Viscoelastic properties of polymers, 3rd ed. Wiley, New York.nFindley, W. N., and D. B. Peterson. 1958. Prediction of long-time creep with ten-year creep data on four plastic laminates. Proceedings ASTM. 58:841-861.nGoldsmith, V., and P. U. A. Grossman. 1967. The effect of frequency of vibration on the viscoelastic properties of wood. J. Inst. Wood Sci. 18:44-53.nGreenbaum, G. A., and M. F. Rubinstein. 1968. Creep analysis of axisymmetric bodies using finite elements. Nuclear Eng. Design 7:379-397.nGressel, P. 1984. Prediction of long-term deformation behavior from short-term creep experiments. Holz Roh- Werks. 42:293-301.nGrossman, P. U. A. 1971. Use of leicester's rheological model for mechano-sorptive deflections of beams. Wood Sci. Technol. 5:232-235.nGrossman, P. U. A. 1976. Requirements for a model that exhibits mechano-sorptive behavior. Wood Sci. Technol. 10:163-168.nGrossman, P. U. A. 1978. Mechano-sorptive behavior. Pages 282-303 in General constitutive relations for wood and wood-based materials. Report of NSF Workshop.nGrossman, P. U. A, L. D. Armstrong, and R. S. T. Kingston. 1969. An assessment of research in wood rheology. Wood Sci. Technol. 3:324-328.nGrossman, P. U. A, L. D. Armstrong, R. S. T. Kingston, and R. S. T. Kingston. 1954. Creep and stress relaxation in wood during bending. Australian J. Appl. Sci. 5(4):403-417.nHackett, R. M. 1971. Viscoelastic stresses in a composite system. Polymer Engr. Sci. 11(3).nHann, R. A. et al. 1970. Moisture content of laminated timbers. U.S.D.A. Forest Service Research Paper FPL149, For. Prod. Lab.nHayman, B. 1981. Creep buckling—A general view of the phenomena. Pages 289-307 in A. R. S. Ponter and D. R. Hayhurst, eds. Proceedings of the Third IUTAM Symposium on Creep in Structures. Springer-Verlag, Berlin.nHearmon, R. F. S., and J. M. Paton. 1964. Moisture content changes and creep of wood. For. Prod. J. 14(8):357-359.nHenriksen, M. 1984. Nonlinear viscoelastic stress analysis—A finite element approach. Computers and Structures 18(1):133-139.nHiel, C., A. H. Cardon, and H. F. Brinson. 1984. The nonlinear viscoelastic response of resin matrix composite laminates. NASA Contractor Report 3772.nHolzer, S. M., and J. R. Loferski. August 1987. Background for research on glulam lattice domes. Pages 305-318 in Proceedings of the Sixth Annual Structures Congress. ASCE Structural Division, Orlando, Florida.nHoyle, R. J., Jr., M. C. Griffith, and R. Y. Itani. 1985. Primary creep in Douglas-Fir beams of commercial size and quality. Wood Fiber 17(3):300-314.nHumphries, M., and A. P. Schniewind. 1982. Behavior of wood columns under cyclic relative humidity. Wood Sci. 15(1):44-48.nItani, R. Y., M. C. Griffith, and R. J. Hoyle, Jr. 1986. The effect of creep on long wood column design and performance. J. Struc. Eng. 112(5):1097-1114.nJohnson, J. A. 1978. Review of the interaction of mechanical behavior with moisture movement of wood. Pages 282-303 in General constitutive relations for wood and wood-based materials. Report of NSF Workshop.nKabir, A. F. 1976. Nonlinear analysis of reinforced concrete panels, slabs, and shells for time dependent effects. Ph.D. dissertation, University of California, Berkeley.nKing, E. J., Jr. 1961. Time-dependent strain behavior of wood in tension parallel to grain. For. Prod. J. 11(3): 156-165.nKingston, R. S. T., and B. Budgen. 1972. Some aspects of the rheological behavior of wood, part iv: Nonlinear behavior at high stresses in bending and compression. Wood Sci. Technol. 6:230-238.nKingston, R. S. T., and L. N. Clarke. 1961. Some aspects of the rheological behavior of wood. I. The effect of stress with particular reference to creep. Australian J. App. Sci. 12(2):211-227. II. Analysis of creep data by reaction-rate and thermodynamic methods. 12(2):227-240.nKitahara, K., and K. Yukawa. 1964. The influence of change in temperature on creep in bending. J. Jap. Wood Res. Soc. 10(5):169-175.nKraus, H. 1980. Creep analysis. Wiley, New York.nKuipers, J. 1977. Long duration tests on timber joints. CIB-W18, Stockholm. February.nLeicester, R. H. 1971. Large deflections of timber beam-columns during drying. Wood Sci. Technol. 5(3):221-231.nLeicester, R. H, G. F. Reardon, and K. B. Schuster. 1980. Toothed-plate connector joints subjected to long duration loads. IUFRO. April. Oxford.nMack, J. J. 1962. Creep in nailed joints. Nature (London) 193(4822):1313.nMack, J. J. 1965. A study of creep in nailed joints. CSIRO, Australia, Div. Forest Prod. Tech. Paper No. 27.nMendelson, A., M. H. Hirschberg, and S. S. Manson. 1959. A general approach to the practical solution of creep problems. J. Basic Eng., ASME 81:585-598.nMukudai, J. 1983. Evaluation of linear and non-linear viscoelastic bending loads of wood as a function of prescribed deflections. Wood. Sci. Technol. 17:203-216.nMukudai, J, and S. Yata. 1986. Modeling and simulation of viscoelastic behavior (tensile strain) of wood under moisture change. Wood. Sci. Technol. 20:335-348.nMukudai, J, and S. Yata. 1987. Further modeling and simulation of viscoelastic behavior (bending deflection) of wood under moisture change. Wood. Sci. Technol. 21:49-63.nNakai, T., and P. U. A. Grossman. 1983. Deflection of wood under intermittent loading. Wood. Sci. Technol. 17:55-67.nNational Design Specifications For Wood Construction. 1986. National Forest Products Assoc., Washington, D.C.nNickell, R. E. 1974. Thermal stress and creep. Pages 103-122 in W. D. Pilkey et al., eds. Structural mechanics computer programs. University Press of Virginia, Charlottesville.nNilson, A. H. (Chairman) et al. 1982. State-of-the-art report on finite element analysis of reinforced concrete. American Society of Civil Engineers.nNoren, B. 1968. Nailed joints—Their strength and rigidity under short-term and long-term loading. Report 22, Swedish Forest Products Research Laboratory, Stockholm.nOviatt, A. E., Jr. 1968. Moisture content of glulam timbers in use in the Pacific Northwest. Pacific Northwest Forest and Range Experiment Station, Forest Service, U.S.D.A.nPentoney, R. E., and R. W. Davidson. 1962. Rheology and the study of wood. For. Prod. J. 12: 243-248.nPolensek, A. 1982. Creep prediction for nailed joints under constant and increasing loading. Wood Sci. 15(2): 183-192.nPovolo, F., and M. Fontelos. 1987. Time-temperature superposition principle and scaling behavior. J. Materials Sci. 22(5): 1530-1534.nRanta-Maunus, A. 1975. The viscoelasticity of wood at varying moisture content. Wood. Sci. Technol. 9:189-205.nSchaffer, E. L. 1972. Modeling the creep of wood in a changing moisture environment. Wood Fiber 3(4):232-235.nSchaffer, E. L. 1982. Influence of heat on the longitudinal creep of dry Douglas-Fir. Pages 20-52 in R. W. Meyer and R. M. Kellog, eds. Structural uses of wood in adverse environments. Society of Wood Science and Technology. Van Nostrand Reinhold Company, New York.nSchapery, R. A. 1966. A theory of nonlinear thermoviscoelasticity based on irreversible thermodynamics. Pages 511-530 in Proceedings of the Fifth U.S. National Congress of Applied Mechanics. ASME.nSchniewind, A. P. 1967. Creep-rupture life of Douglas-Fir under cyclic environmental conditions. Wood. Sci. Technol. 1(4):278-288.nSchniewind, A. P. 1968. Recent progress in the study of the rheology of wood. Wood. Sci. Technol. 2:188-206.nSchniewind, A. P, and J. D. Barrett. 1972. Wood as a linear orthotropic viscoelastic material. Wood. Sci. Technol. 6:43-57.nSchniewind, A. P, and D. E. Lyon. 1973. Further experiments on creep-rupture life under cyclic environmental conditions. Wood Fiber 4(4):334-341.nSenft, J. F., and S. K. Suddarth. 1971. An analysis of creep-inducing stress in Sitka spruce. Wood Fiber 2(4):321-327.nSharifi, P., and D. N. Yates. 1974. Nonlinear thermo-elastic-plastic and creep analysis by the finite element method. AIAA Journal 12:1210-1215.nSnyder, M. D., and K. J. Bathe. 1981. A solution procedure for thermo-elastic-plastic and creep problems. Nuclear Eng. Design. 64:49-80.nSperling, L. H. 1986. Introduction to physical polymer science. Wiley, New York.nTang, R. C. 1980. Viscoelastic behavior of wood in changing environments. Workshop Proceedings on How the Environment Affects Lumber Design: Assessments and Recommendations. U.S. Forest Service For. Prod. Lab.nTriax Domes. 1975. Glued-laminated wood structural systems for clear-span circular buildings. Glue Laminated Wood, 6. Koppers Company, Inc., Pittsburgh, PA.nUrakami, H., and K. Nakato. 1966. The effect of temperature on torsional stress relaxation of wet hinoki wood. J. Jap. Res. Soc. 12(3):118-123.nVarax Domes. Specifications. Section 13500 Varax Dome Structure and Roof Decking. Western Wood Structures Inc. Tualatin, Oregon.nWhale, L. R. 1988. Deformation characteristics of nailed or bolted joints subjected to irregular short or medium term lateral loading. Ph.D. dissertation, South Bank Polytechnic Institute, London, UK.nWilkinson, T. L. 1984. Longtime performance of trussed rafters with different connection systems. U.S.D.A. Forest Service, For. Prod. Lab. Research Paper FPL444.nWood, L. W. 1951. Relation of strength of wood to duration of load. U.S. Forest Service, For. Prod. Lab. Report No. R1916.nYlinen, A. 1965. Prediction of the time-dependent elastic and strength properties of wood by the aid of a general nonlinear viscoelastic rheological model. Holz Roh- Werks. 23:193-196.nZahn, J. J. 1987. Discussion of the effect of creep on long wood column design and performance. J. Struct. Eng. 113(9):2100-2102.nZhurkov, S. N. 1965. Kinetic concept of the strength of solids. Intl. J. Fracture Mechanics. Vol. 1.nZienkiewicz, O. C., and I. C. Cormeau. 1974. Viscoplasticity-plasticity and creep in elastic solids— A united numerical approach. Intl. J. Num. Meth. Engng. 8:821-845.nZienkiewicz, O. C., and M. Watson. 1966. Some creep effects in stress analysis with particular reference to concrete pressure vessels. Nuclear Engineering and Design 4:406-412.n

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Published

2007-06-22

Issue

Number 4 / October 1989

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Research Contributions

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