Skip to main content
Journal of Wood Science

Official Journal of the Japan Wood Research Society

Download PDF
  • Original article
  • Published:

Bending creep behavior of wood under cyclic moisture changes

Journal of Wood Science volume 45, pages 113–119 (1999)Cite this article

Abstract

This study examined the bending creep behavior in the longitudinal direction of six species under cyclic moisture content (MC) changes. For each species, tests were made at 20°C with five cyclic relative humidity changes between 65% and 95%, beginning from moisture adsorption. A load corresponding to 25% of short-term breaking load of the species was applied to the radial section of each specimen with four-point bending. The effect of MC change on instantaneous compliance was also investigated under the same condition. The quantitative relation between mechano-sorptive (MS) compliance and MC change was examined, and the material parameter KM for the relation in specific sorption was determined. Results indicated that the total compliance in the six species with different behavior increases with sorption time. As an integral part of total compliance, instantaneous compliance changes linearly with MC and influences to a greater or lesser extent the total compliance behavior. In general, with increasing MC change, the MS compliance linearly increases during the first adsorption and all desorption and decreases slightly during subsequent adsorption. The material parameterK M varies markedly not only with species but also with specific sorption. The first adsorption causes the largest deformation, followed by desorption.

References

  1. Armstrong LD, Kingston RT (1962) The effect of moisture content changes on the deformation of wood under stress. Aust J Appl Sci 13:257–276

    Google Scholar 

  2. Schniewind AP (1968) Recent progress in the study of rheology of wood. Wood Sci Technol 2:188–206

    Google Scholar 

  3. Armstrong LD (1972) Deformation of wood in compression during moisture movement. Wood Sci 5:81–86

    Google Scholar 

  4. Grossman PUA (1976) Requirements for a model that exhibits mechano-sorptive behavior. Wood Sci Technol 10:163–168

    Article  Google Scholar 

  5. Hearman RFS, Paton JM (1964) Moisture changes and creep of wood. For Prod J 14:357–359

    Google Scholar 

  6. Rice RW, Youngs RL (1990) The mechanism and development of creep during drying of red oak. Holz Roh Werkstoff 48:73–79

    Article  Google Scholar 

  7. Wu Q, Milota MR (1995) Rheological behavior of Douglas-fir at elevated temperature. Wood Fiber Sci 3:285–295

    Google Scholar 

  8. Wu Q, Milota MR (1996) Mechano-sorptive deformation of Douglas-fir specimens under tangential tensile stress during moisture adsorption. Wood Fiber Sci 1:128–132

    Google Scholar 

  9. Norimoto M, Gril J (1989) Wood bending using microwave heating. J. Microwave Power Electromag Energy 24:203–212

    Article  Google Scholar 

  10. Iida I, Norimoto M, Imamura Y (1983) Wood bending utilizing microwave heating hygrothermal recovery of bentwood in the direction perpendicular to grain (in Japanese). Wood Res 17:99–111

    Google Scholar 

  11. Nakano T (1996) A theoretical description of creep behavior during water desorption. Holzforschung 50:49–54

    Article  CAS  Google Scholar 

  12. Hunt DG (1984) Creep trajectories for beech during moisture changes under load. J Mater Sci 19:1456–1467

    Article  CAS  Google Scholar 

  13. Leicester RH (1971) A theological model for mechano-sorptive deflections of beams. Wood Sci Technol 5:211–220

    Article  Google Scholar 

  14. Ranta-Maunus A (1975) The viscoelasticity of wood at varying moisture content. Wood Sci Technol 9:189–205

    Article  Google Scholar 

  15. Gerhards CC (1982) Effect of moisture content and temperature on the mechanical properties of wood: an analysis of immediate effect. Wood Fiber 14(1):4–36

    Google Scholar 

  16. Tokumoto M (1994) Creep and set in the non-equilibrium states of moisture (in Japanese). Mokuzai Gakkaishi 40:1157–1164

    Google Scholar 

  17. Hunt DG (1986) The mechano-sorptive creep susceptibility of two softwoods and its relation to some other materials properties. J Mater Sci 21:2088–2096

    Article  CAS  Google Scholar 

  18. Armstrong LD, Christensen GN (1961) Influence of moisture change on deformation of wood under stress. Nature 191:869–870

    Article  Google Scholar 

  19. Armstrong LD, Kingston RT (1960) Effect of moisture change on creep in wood. Nature 185:862–863

    Article  Google Scholar 

  20. Lu W, Erickson RW (1994) The effect of directed diffusion on the mechano-sorptive creep of small redwood beam. For Prod J 44(1):8–14

    Google Scholar 

  21. Erins PV, Cinite V, Jakobson M (1976) Wood as a crosslinked, multicomponent polymer system. In: Applied Polymer Symposium No. 28. ACS, pp 1117-1138

  22. Hunt DG (1997) Dimensional changes and creep of spruce, and consequent model requirements. Wood Sci Technol 31:3–16

    Article  CAS  Google Scholar 

  23. Nakano T (1996) Viscosity and entropy change in creep during water desorption for wood. Wood Sci Technol 30:117–125

    Article  CAS  Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Laboratory of Plant Materials, Faculty of Agriculture, Tokyo University of Agriculture and Technology, 183-8509, Tokyo, Japan

    Yaguang Zhou, Masami Fushitani & Takafumi Kubo

  2. Yamanashi Forestry and Forest Products Research Institute, 400-0502, Yamanashi, Japan

    Masayuki Ozawa

Authors
  1. Yaguang Zhou
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Masami Fushitani
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Takafumi Kubo
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Masayuki Ozawa
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Yaguang Zhou.

Additional information

This paper was presented at the 48th annual meeting of the Japan Wood Research Society in Shizuoka, Japan. April 1998

Rights and permissions

Reprints and permissions

About this article

Cite this article

Zhou, Y., Fushitani, M., Kubo, T. et al. Bending creep behavior of wood under cyclic moisture changes. J Wood Sci 45, 113–119 (1999). https://doi.org/10.1007/BF01192327

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF01192327

Key words