INFLUENCE OF THE SPECIMEN SIZE AND TEST SPEED IN STATIC BENDING STRENGTH OF THREE TROPICAL WOOD SPECIES
DOI:
https://doi.org/10.5902/1980509818461Keywords:
mechanical properties, test speed, specimen size, flexural strengthAbstract
http://dx.doi.org/10.5902/1980509818461
This paper discusses the influence of different test speeds and specimen sizes, free of defects, in determining the bending strength of three Brazilian woods. Its importance lies in the possibility of establishing methods of characterization with smaller specimens and higher speeds, resulting in time saving and cost reduction in transport, without loss of quality and precision in results. Traditionally, tests with small variations of speed and specimen size have been little discussed, possibly due to the lack of interest in changing methodologies which are already established. The methodology used here involved the static bending with moisture content at 12%, five specimen sizes and three test speeds. The species characterized were: cumaru (Dipterix odorata), jequitibá (Allantoma lineata) and quaruba (Vochyisia guianensis). References on dimensions and speeds were selected based on the Comisión Panamericana de Normas Técnicas (COPANT 555/73). These standards establish procedures for determining the physical and mechanical properties of wood species, free of defects, using small specimen sizes. The results showed a significant influence of specimen size and no influence of the velocities in the tests for determining the bending properties of the species featured. In conclusion, to maintain compatibility with the already published results, using this standard is not recommended to change the specimen dimensions but the current test speed can be increased within the limits studied.
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References
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