Moment-Curvature Analysis of Coupled Bending and Mechanosorptive Response of Red Spruce Beams
Keywords:
Bending, creep, mechanosorption, modeling, spruce, compression, tensionAbstract
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.References
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