Estudo do comportamento mecânico de madeira laminada colada de Hevea brasiliensis produzida com adesivo poliuretano

The aim of this work was to evaluate the properties of rubber wood (Hevea brasiliensis) for the \nproduction of structural pieces of glued laminated timber. Six trees with ages of approximately \n12 years and diameter at breast height (DBH) greater than 25 cm were felled. Glued laminated timber \nbeams were produced with three layers measuring 6.0 × 2.0 × 120.0 cm per beam, in a total of 6 beams, \nusing the one-component polyurethane adhesive. The moisture, apparent density and porosity of the \nsolid wood were determined. The modulus of elasticity (MOE), the modulus of rupture (MOR), shear \nstrength (single and double line), delamination and visualization of the glue line were determined by \nmeans of photomicrographs of the laminated wood samples. The values of the analyzed properties \nwere close to the species traditionally used for the production of beams of glued laminated wood, \nmeeting the minimum requirements for this purpose according to the norms NBR 7190 and JAS 234 \nfor MOR (30 MPa) and for single and double glue line shear strength (5.40 MPa) in the dry condition.