Propriedades tecnológicas de vigas de madeira laminada colada produzidas com louro-vermelho: (sextonia rubra)

AUTOR(ES)
DATA DE PUBLICAÇÃO

2009

RESUMO

The objective of this study was characterize the technological behavior of glulam beams (MLC) using the wood from Louro Vermelho (Sextonia rubra Lauraceae), through the evaluation of the adhesion with adhesive resorcinol-formaldehyde and evaluate theoretically and experimental the modulus of elasticity (EM), the modulus of rupture (fM), the bending moment (M) and the deflection (δ) of MLC beams produced with nondestructive classified lumbers. The performance of the adhesion was evaluated by shear in glue line, tension perpendicular of glue line, and in tension parallel to grain with scarf joint, as indicated by the standard NBR 7190 (1997). In order to study the effect of spread rate of the adhesive on the quality of glued line, three spread of rate (200, 300 and 400 g/m) were evaluated. The lumbers were classified mechanically and was being evaluated the dynamic modulus of elasticity, using two non-destructive techniques, stress wave transmission (ESW) and by transverse vibration (ETV). Parallel, bending tests were conducted to determine the static modulus of elasticity (E), according to ASTM D4761. After that, relations between the dynamic modulus of elasticity and static were compared and analyzed by linear regressions, and their properties used in the composition of the beams and in theoretical models. The beams were produced and tested in static bending, according to ASTM D 198. The spread of rate of 300 g/m was statistically identical as 400 g/m, witch was indicated to produce glulam beams. It was found that theoretical model showed good predictability and significance. The transverse vibration technique is viable to classify the lumber as well the glulam beams. The wood of louro vermelho is indicated for use in glulam beams.

ASSUNTO(S)

madeira laminada colada (mlc) adesivos de madeira propriedades mecânicas ensaios não-destrutivos (end) ciencias agrarias

ACESSO AO ARTIGO

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