&lt;b&gt;Evaluation of modulus of elasticity in static bending of particleboards manufactured with &lt;i&gt;Eucalyptus grandis&lt;/i&gt; wood and oat hulls

Luciano Donizeti Varanda,Diego Henrique De Almeida,Diogo Aparecido Lopes Silva,André Luis Christoforo,Túlio Hallak Panzera,Francisco Antonio Rocco Lahr

doi:10.4025/actascitechnol.v36i3.21077

Abstract

The aim of this study was to determine the modulus of elasticity (MOE) in static bending using two different calculation methods, a simple one based on Brazilian standard ABNT NBR 14810 (ABNT, 2006), and an alternative one, based on the Least Squares Method, and evaluate whether there is statistical equivalence between these MOE calculation methods. The alternative method employed results obtained from static bending tests at three-points, with three dial gauges, non-destructively, by imposing limits on two displacements (L 300 -1 and L 200 -1 ), where L is the specimen length. Results of confidence intervals indicated statistical equivalence between MOE values obtained by means of both methods, thus corroborating the simple mathematical model proposed by ABNT NBR14810 (ABNT, 2006). Panels produced with up to 15% oat hulls (Treatments 1 to 6) showed the highest average MOE values. The methods employed to obtain MOE in static bending were statistically equivalent. However, in addition to being non-destructive, the alternative method proposed here in provided more reliable results, just by taking into account more measures along the specimens.

Highlights

Wood-based panels have been widely used around the world in various segments of the timber industry
This study aimed to evaluate the hardness of panels manufactured with Eucalyptus grandis wood particles and oat hulls by an alternative means, based on the least squares method and mechanics of materials, similar to what was done by Christoforo et al (2012), and compare the modulus of elasticity (MOE) results obtained with those obtained through the method found in Brazilian standard ABNT NBR 14810 (ABNT, 2006), adapted to non-destructive testing
300-1,and Em corresponding to the six specimens for each one of the twelve treatments (T) are presented in According to Table 2, the panels manufactured with up to 15% oat hulls provided the highest average MOE values

Summary

Introduction

Wood-based panels have been widely used around the world in various segments of the timber industry. Alternative raw materials have been systematically investigated in order to reduce the demand for wood particleboard production In the segment of wood products, special attention should be given to woodbased panels, because they constitute an essential raw material for a range of industrial applications. 405-411, July-Sept., 2014 construction industries are the main driving forces for technological development of the particleboard industry. The most commonly employed tests to evaluate mechanical properties of particleboards are of the destructive kind. New non-destructive methods are being devised to evaluate properties of wood and its byproducts. Among them are methods that employ stress wave, electrical properties, ultrasound, deflection, gamma radiation, near infrared spectroscopy, and X-ray (MENDES et al, 2012)

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Conclusion