摘要

In response to the great world-wide pressure to preserve the Amazon Forest, native species planted forests are growing and becoming economically viable in the northern region of Brazil. Amongst the diverse planted species, parica (Schizolobium Amazonicum Huber ex. Ducke) is considered as a pioneer species. The main objective of this paper was to study the glued laminated timber (GLT) beams performance within this species; using adhesives of Resorcinol Formal-dehyde and Emulsion Polymerized isocyanate commercialized in Brazil. The pieces were graded by non-destructive test (ultra-sound) the laminated board with larger dynamic modules of elasticity being used, on the upper third face and lower third face of the beams. Timber beams of parica were selected randomly for comparing the performances. The strength tests were four-point bending, verifying the shear and tension strenght of the glue lines, too. It was verified, with 95% of confidence, that all beams have the same performance. The shear rupture values were smaller than the glue lines strength (resorcinol-formaldehyde adhesive by 2,97 MPa and isocyanate by 2,91 MPa). Based on these values, it is possible to recommend this species for producing GLT beams with C-20 strength class design as having a compatible performance to timber beams.

  • 出版日期2010-9