Moment-Curvature Analysis of Coupled Bending and Mechanosorptive Response of Red Spruce Beams


  • Rastislav Lagaňa
  • William G. Davids
  • Lech Muszyński
  • Stephen M. Shaler


Bending, creep, mechanosorption, modeling, spruce, compression, tension


In this study, an expanded comprehensive numerical approach to predict hygromechanical behavior of beams is proposed that rigorously couples spatially varying time-dependent moisture content fluctuation with uniaxial stress-strain relations. The constitutive model, consisting of elastic, viscoelastic, and two mechanosorptive strain elements connected in series, was used in a layered moment-curvature flexural analysis. The procedure is numerical and is able to take into account effect of moisture content changes, different mechanosorptive behavior in tension and compression, and cross-sectional hygroexpansion. The overall trend and magnitude of predicted deflections are in good agreement with experimental results. Results demonstrated that complex beam behavior in a varying environment can be predicted by a simple model with well-defined material characteristics generated through relatively simple 18-h uniaxial experiments.


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Research Contributions