Effect of nondestructive testing of laminations on the bending properties of glulam beams made from louro-vermelho (Sextonia rubra)

Ricardo Faustino Teles,Frederico De Souza,Mário Rabelo De Souza,Cláudio Henrique Soares Del Menezzi

doi:10.1590/s0104-77602010000100009

Ricardo Faustino Teles, Frederico De Souza + Show 2 more

Open Access

https://doi.org/10.1590/s0104-77602010000100009

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Journal: CERNE	Publication Date: Mar 1, 2010
Citations: 9	License type: cc-by

Affiliation: Instituto Florestal, Universidade de Brasília

Abstract

This work aims to assess the bending properties of glued laminated timber beams (glulam) manufactured with species louro-vermelho (Sextonia rubra). Laminations were nondestructively tested using the transverse vibration method (E Mlam). Then 10 glulam beams were manufactured and tested in static bending according to ASTM D 198 standard, having modulus of elasticity (E M), modulus of rupture (fM), and bending moment (M) determined. The finished beams were also tested by the transverse vibration method (E Mvt). It was noted that the E Mvt value was only 2% lower than the E M value. Using laminations with a high modulus of elasticity did allow effective gain in stiffness. Therefore, results indicate that the transverse vibration method is a valid, reliable technique both for testing glulam laminations and for assessing stiffness in finished beams. Bending properties in glulam beams were influenced by the stiffness of constituent laminations.

Highlights

In Brazil, the diversity of wood species is significant and has great potential awaiting exploration
With the above in mind, this study aims to evaluate the bending properties of glued laminated timber beams made from louro-vermelho (Sextonia rubra) whose member laminations had been pretested using the transverse vibration method
The bending properties of glulam beams were significantly influenced by the stiffness of constituent laminations, which means that the use of stiffer laminations is reflected in stiffer, stronger glulam beams

Summary

Introduction

In Brazil, the diversity of wood species is significant and has great potential awaiting exploration. For suitable use of wood as structural material, knowledge of its strength and stiffness characteristics is indispensable. This should happen with all species, including alternative species whose potential is more promising, considering the wealth of use possibilities they offer. Under this scenario, new manufacture technologies and research have been developed for use of wood in building construction. Known in literature as glulam, can be an alternative for rational use of sawn wood as a possible, compatible solution for a vast range of structural problems. Brazil only boasts a few manufacturing plants in the sector, yet a significant number of academic works have been developed over the past 10 years attempting to improve information available on the subject (FIORELLI 2005, GROHMANN & SZÜCS 1998, NASCIMENTO et al 2002, ZANGIÁCOMO 2003)

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