Abstract
This paper deals with the modeling of linear viscoelastic behavior and strain accumulation (accelerated creep) during moisture content changes in timber. A generalized Kelvin–Voigt model is used and associated in series with a shrinkage-swelling element depending on the mechanical and moisture content states of materials. The hygrothermal aging due to climatic variations implies an evolution of rheological parameters depending upon moisture content and temperature. Two distinct viscoelastic laws, one for drying and the other for moistening, are coupled according to the thermodynamic principles when wood is subjected to nonmonotonous moisture variations. An incremental formulation of behavior is established in the finite element program CAST3M (Software developed by C.E.A. (Commissariat á l'Energi Atomique) and an experimental validation from tension creep-recovery tests is presented.
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Dubois, F., Randriambololona, H. & Petit, C. Creep in Wood Under Variable Climate Conditions: Numerical Modeling and Experimental Validation. Mech Time-Depend Mater 9, 173–202 (2005). https://doi.org/10.1007/s11043-005-1083-z
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DOI: https://doi.org/10.1007/s11043-005-1083-z