Despite the diverse use of wood in industrial construction, some technological properties of tropical wood species are still little known. This concerns more particularly the logarithmic decrement, viscous damping ratio, loss factor, quality factor and specific damping ratio, which were little studied and documented in the literature, which hinders the reliable design of structures under dynamic solicitation. This study describes a non-destructive method for determining the damping properties of wood. It was based on the analysis of the attenuation of the free transverse vibrations of a fixed support-free specimen following excitation. Cameroonian forests abound with important species that were much in demand for structural applications and were often subjected to dynamic loads. However, in the literature and in the available databases, very little information was available on the vibration properties of these wood species. To solve this problem, three specimens of twenty-four wood species with a cross-section of 10 mm × 20 mm, with a length of 1600 mm, were prepared and subjected to a free vibration test in the fixed support-free configuration. The accelerations as a function of time were obtained. Displacement data were derived from recorded accelerations, and the logarithmic decrement was calculated using the first twenty-one amplitude peaks. Using known relationships between parameters, the viscous damping ratio, loss factor, quality factor and specific damping ratio were deduced. The results obtained were relatively variable between species. Among the studied wood species, Azobé exhibited the highest damping ratio, while Wengé showed the lowest. Compared with the data available in the literature for the same species, there was a considerable difference.
Author
(s) Details
Nkibeu Jean Bertin
Laboratory Civil Engineering and Mechanics, National Advanced School of
Engineering, The University of Yaoundé 1, Cameroon.
Makomra Valentin
Department of Civil Engineering, National Advanced School of Public Works,
Cameroon.
Moussa Sali
Laboratory of Materials, Mechanics and Civil Engineering, National Advanced
School of Engineering, The University of Maroua, Cameroon and Department of
Civil Engineering, Advanced Teachers Training College of the Technical
Education, The University of Douala, Cameroon.
MadjaDoumbaye Jerémie
Department of Civil Engineering, National Advanced School of Public Works,
Cameroon.
Please see the book here:- https://doi.org/10.9734/bpi/erpra/v8/5605
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