Influence of the age and of the radial position on static of the wood of Eucalyptus grandis Hill. ex. Maiden

Submitted by Morgana Andrade (morgana.andrade@ufes.br) on 2011-01-26T13:25:31Z No. of bitstreams: 2 a14v29n5.pdf: 206783 bytes, checksum: ecc37fe43f7dc35b6e4a5a56c1ed68e6 (MD5) license_rdf: 19615 bytes, checksum: 3aa521fc87b9644c1a6a745f9ad20bea (MD5) Approved for entry into archive by Patricia Barros(patricia.barros@ufes.br) on 2011-02-08T20:38:18Z (GMT) No. of bitstreams: 2 a14v29n5.pdf: 206783 bytes, checksum: ecc37fe43f7dc35b6e4a5a56c1ed68e6 (MD5) license_rdf: 19615 bytes, checksum: 3aa521fc87b9644c1a6a745f9ad20bea (MD5) Made available in DSpace on 2011-02-08T20:38:18Z (GMT). No. of bitstreams: 2 a14v29n5.pdf: 206783 bytes, checksum: ecc37fe43f7dc35b6e4a5a56c1ed68e6 (MD5) license_rdf: 19615 bytes, checksum: 3aa521fc87b9644c1a6a745f9ad20bea (MD5) Previous issue date: 2005-09 Este trabalho objetivou testar a variação da flexão estática da madeira de Eucalyptus grandis, ao longo da seção radial e sob quatro diferentes idades (10, 14, 20 e 25 anos), provenientes de talhões comerciais. As amostras foram retiradas da prancha diametral, de cada uma das 16 árvores (quatro para cada idade), tomadas de quatro posições eqüidistantes (0, 33, 66 e 100%), no sentido medula-casca, com oito repetições por posição. Verificou-se que os módulos de elasticidade (MOE) e de ruptura (MOR) apresentaram valores médios de 129.230 kgf/cm2 e 854 kgf/cm2, respectivamente, e ambos se mostraram positivamente correlacionados com a idade e com a posição radial, no sentido medula-casca. Os maiores valores foram conseguidos nas madeiras de 20 anos de idade e localizadas na região mais próxima da casca. ABSTRACT The objective of this work was to study the static bending variation of Eucalyptus grandis wood along the radial plane at four different ages (10 - 14 20 and 25 years), from commercial stands. The samples were removed from a diametrical board on each of sixteen trees (four from each age); taken from four equidistant positions (0, 33, 66 and 100%), in the pith-to-bark direction, with six replicates per position. It was found that the elasticity modulus (MOE) showed mean values of 129.230 kgf/cm2, and the rupture modulus (MOR) showed mean values of 854 kgf/cm2, both showing to be positively correlated with age and radial position in the pith-to-bark direction. The greatest values were obtained from twenty-year-old wood and located near the bark.