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EVALUATION OF PHYSICAL AND MECHANICAL PROPERTIES OF JATOBÁ (Hymenaea stilbocarpa Hayne) WOOD WITH DIFFERENT LEVELS OF MOISTURE CONTENT AND DIFFERENT REGIONS OF EXTRACIONS

ABSTRACT

This research aimed to investigate the influence of the extraction regions (Caracarí and Bonfim municipalities - South of Roraima; Alta Floresta municipality - North of Mato Grosso) of Jatobá (Hymenaea stilbocarpa) wood. The moisture content (saturated wood at 12%) was also evaluated in fifteen physical and mechanical properties of interest. Altogether, 840 samples were prepared and tested, according to the requirements of the Brazilian standard ABNT NBR 7190. ANOVA results (at 5% significance level) showed that the extraction region of the samples was not significant in the physical and mechanical properties evaluated, since equivalent values were obtained regardless of location, highly interesting aspect to the extent that it is not always possible to identify the extraction region of the tropical hardwood. This importance is even greater in the case of the use of wood as an element, the reference values of which are pointed out in the Annexes of the Brazilian standard. With respect to the moisture content, a significant difference was noted in only eight of the fifteen evaluated properties. The condition of 12% of moisture content showed mean values higher than the saturated condition in the strength properties in the parallel compression (37%), resistance in parallel tension (29%) and shear (36%) strength in the direction parallel to the grain, bending strength (26%), elasticity modulus in parallel compression (9%) and 200 parallel directions (35%) and normal (28%) directions to the grain, and lower in bulk density.

Keywords:
Wood; Moisture content; Region of origin

Sociedade de Investigações Florestais Universidade Federal de Viçosa, CEP: 36570-900 - Viçosa - Minas Gerais - Brazil, Tel: (55 31) 3612-3959 - Viçosa - MG - Brazil
E-mail: rarvore@sif.org.br