Estudo do efeito da autoclavagem no desempeno e nas propriedades mecânicas da madeira da espécie mangue

Abstract

Currently, one of the major problems faced by humanity is the deforestationof forests, in order to obtain wood for various purposes, with thecivil construction sector being one of the main responsible for its consumption, mainly in the production of molds for concreting structural elements. Thesewoods, after being used in concreting, are usually warped, making it practicallyimpossible to reuse them for new concreting, causing them to be discarded. Inthis way, finding solutions aimed at reusing these woods becomes essential. Inthis context, a technique that can be successful in straightening these woodsisthe use of autoclaving, which is a process that allows the wood to beheatedwithout the risk of combustion. However, this process can changeitsmechanical properties. Thus, this research aimed to use autoclaving as awoodstraightening technique, as well as to evaluate whether this process altersthemechanical properties of modulus of rupture in flexion and modulus of elasticity. The wood used for this study was of the mangue species. Specimens wereproduced, whose Flexural and Elasticity modulus tests were adapted fromtheASTM D 143 – 94 standard and tested in the condition of natural humidityandsaturated humidity. The straightening test was performed by bendingthespecimens by applying force and measuring the displacements in relationtothemid-span of the specimens and again measured after autoclaving andaddingweight. Analyzes of variance were performed to verify whether the adoptedprocedures were significant. The results showed that the autoclaving processsignificantly decreases the values of modulus of rupture and modulusof elasticity, but also provided a significant decrease in the warping of thetest specimens with the use of weights, suggesting that the autoclaving processcanbe a tool for straightening the woods for a new use in concreting.