Abstract
The creep of wood in the grain direction is of major importance when deflections of structures are considered. Less studied is the creep in directions perpendicular to the grain, which is of interest when drying stresses and the cracking of wood are analysed. Experimental results obtained during 1987–1991 are reported. These included tensin, bending and some compression tests under constant and varying humidity at temperatures of 20–80°C. The results indicate that mechano-sorptive creep is still more important in directions perpendicular to the grain than in the longitudinal direction. Creep is also greatly dependent on the temperature.
Resume
Le fluage du bois dans la direction du grain est de première importance quand on examine les flèches des structures. Moin étudié, le fluage dans des directions perpendiculaires est intéressant pour l’analyse des contraintes et de la fissuration du bois.
On rend compte ici des résultats expérimentaux obtenus au VTT entre 1987 et 1991: essais en traction, en flexion et en compression avec une teneur en humidité constante et variable à des teneur en humidité constante et variable à des températures de 20 à 80°C.
Les résultats indiquent que le fluage mécano-sorptif est encore plus important dans des directions perpendiculaires au grain que dans la direction longitudinale. Le fluage varie aussi beaucoup avec la température.
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Ranta-Maunus, A. Rheological behaviour of wood in directions perpendicular to the grain. Materials and Structures 26, 362–369 (1993). https://doi.org/10.1007/BF02472962
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DOI: https://doi.org/10.1007/BF02472962