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Longitudinal moisture-shrinkage coefficients of softwood at the mechano-sorptive creep limit

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Summary

An adaptor for the conversion of a high-accuracy tensile creep machine to compression loading is described. It was found that a stable mechano-sorptive creep limit could be obtained by a suitable load reduction after moisture cycling; after which further creep and creep recovery just balanced each other. In this stable state the value of the longitudinal moisture-swelling coefficient depended on the strain; being less with tensile strain and more with compressive strain then in the unloaded condition. These differences in the swelling coefficient could explain the apparent recovery during subsequent sorptions in mechanosorptive creep in bending. Such a hypothesis was strongly supported by numerical comparisons of strains in bending, tension and compression.

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Authors and Affiliations

  1. Department of Mechanical Engineering Design and Production, South Bank Polytechnic, Borough Road, SE1 0AA, London

    D. G. Hunt

  2. Bevplate Ltd, Rectory Farm Road, BN15 0DP, Sompting, Lancing

    C. F. Shelton

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  1. D. G. Hunt
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  2. C. F. Shelton
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Additional information

Part of the equipment used in this project was purchased with a grant from the U.K. Science and Engineering Research Council

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Hunt, D.G., Shelton, C.F. Longitudinal moisture-shrinkage coefficients of softwood at the mechano-sorptive creep limit. Wood Sci.Technol. 22, 199–210 (1988). https://doi.org/10.1007/BF00386014

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  • DOI: https://doi.org/10.1007/BF00386014

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