Physical and mechanical properties of LVL panels made from Eucalyptus grandis

O presente trabalho teve como objetivo principal avaliar as propriedades f\uedsicas e mec\ue2nicas de pain\ue9is LVL (Laminated veneer lumber) confeccionados com l\ue2minas de Eucalyptus grandis , provenientes de reflorestamentos da regi\ue3o de Seng\ue9s, Paran\ue1 - Brasil. Foram confeccionados pain\ue9is LVL de 23 l\ue2minas, de dimens\uf5es comerciais de 2500 mm de comprimento, 1200 mm de largura e espessura nominal de 50 mm (l\ue2minas de 2,4 mm). Em vigas retiradas dos pain\ue9is LVL foram analisadas as propriedades de flex\ue3o est\ue1tica (rigidez e resist\ueancia), nas condi\ue7\uf5es de menor in\ue9rcia (flatwise) e de maior in\ue9rcia (edgewise), compress\ue3o paralela, cisalhamento paralelo nos planos L-X e L-Y e densidade, atendendo \ue0s prescri\ue7\uf5es das normas ASTM-D 5456/4761 e ASTM-D 198/143. Os valores m\ue9dios obtidos para o m\uf3dulo de elasticidade e resist\ueancia \ue0 flex\ue3o est\ue1tica foram, respectivamente, 13114 MPa e 88,76 MPa para o ensaio na condi\ue7\ue3o de menor in\ue9rcia e de, respectivamente, 15871 MPa e 88,63 MPa para o ensaio na condi\ue7\ue3o de maior in\ue9rcia. A densidade aparente (a 12% de umidade) dos pain\ue9is LVL e das l\ue2minas foram, respectivamente, 690 kg/m3 e 649 kg/m3. Os valores m\ue9dios obtidos nos ensaios de compress\ue3o paralela foram 16856 MPa para o m\uf3dulo de elasticidade e 58,05 MPa para a resist\ueancia. Os valores m\ue9dios da resist\ueancia no ensaio de cisalhamento paralelo no plano L-Y e no plano L-X foram 5,96 MPa e 5,91 MPa, respectivamente. Todos esses valores atingiram parcialmente ou ultrapassaram os limites m\ue9dios de refer\ueancia estabelecidos para pain\ue9is LVL e para a madeira s\uf3lida origin\ue1ria, atestando, sobretudo, a qualidade dos pain\ue9is produzidos com essa madeira.This paper mainly aimed to evaluate the physical and mechanical properties of LVL panels made from Eucalyptus grandis , from reforestation at the region of Seng\ue9s, in Paran\ue1 state, Brazil. LVL panels were manufactured using 23 veneers (2,4mm thick each one) in commercial dimension of 2.500 mm long and 1,200 mm wide. The properties of static bending were analyzed (strength and rigidity) in beams of the LVL, in the flatwise and edgewise positions. The properties of compression parallel to grain and shear parallel in the plans L-X and L-Y and density in this LVL panels were also analyzed according to ASTM-D 5456/4761 and ASTM-D 198 codes. The mean values to flatwise bending MOE and MOR were 13114 MPa and 88.76 MPa, respectively, and for edgewise bending MOE and MOR were 15871 MPa and 88.63 MPa, respectively. The density (12%) of the LVL panels and of the veneers were 690 kg/m3 and 649 kg/m3. The mean values to parallel compression MOE and MOR were 16856 MPa and 58.05 MPa, respectively. The mean values of the maximum resistance to shear parallel in the plans L-X and L-Y were 5.96 MPa and 591 MPa, respectively. All these values reached partially or they passed the medium limits of reference (normative codes, researches and commercial catalogs) established for LVL panels and original solid wood, attesting overall the quality of those panels produced with this wood