Evaluation of non-destructive methods of measuring growth stress in Eucalyptus globulus: relationships between strain, wood properties and stress

Abstract For the sustainability of an important renewable resource, such as wood, it is important to significantly increase the efficiency of its processing. A large part of this raw material ends up in the wood processing industry, where it is used for the production of pulp, paper, construction and furniture timber, floors and others. Therefore, it is very important to gain the knowledge needed for optimal valuation of raw wood material, through quality detection and classification into quality classes. There are many defectoscopic methods working on different physical principles. The most familiar of these methods are semi-destructive and non-destructive, as they do not cause damage to the tree or wood during assessment. The aim of this article is to describe, assess and compare known semi-destructive and non-destructive methods for the assessment of wood properties. This article describes basic visual inspection, basic semi-destructive methods (Pilodyn, Resistograph) and advanced semi-destructive methods (SilviScan®, DiscBot®) as well. Non-destructive methods use mostly acoustic wave motion (acoustic, ultrasonic), high-frequency waves (using georadar, microwave) and methods based on visual evaluation (image, laser). At last, there are X–ray methods with the latest technology using three-dimensional (3D) computed tomography (CT). The implementation of modern non-destructive methods is of great importance for the application of principles of Industry 4.0, where these methods provide collecting of data on the material properties, in its entire production flow of log processing.

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Verification of the Use of a Kučera Drill for Testing of Wood Properties

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.898.107 ◽

2021 ◽

Vol 898 ◽

pp. 107-112

Author(s):

Pavel Černý ◽

Romana Halamová ◽

Věra Heřmánková

Keyword(s):

Wood Quality ◽

Wood Properties ◽

Masonry Structures ◽

Destructive Testing ◽

Depth Of Penetration ◽

Initial Experiment ◽

Mortar Strength ◽

Wooden Structures ◽

Non Destructive ◽

Destructive Methods

In common practice, we encounter cases where it is not possible to test the wood quality by destructive methods and it is, therefore, necessary to use non-destructive or semi-destructive methods, especially when the wood is already used in construction. The article deals with the methodology of non-destructive and semi-destructive testing of wooden structures using the methodology commonly used for the diagnosis of masonry structures, where mortar strength is tested using a so-called Kučera drill, and with verification of the applicability of this method in the testing of wood properties. Kučera drill was specially modified for the purpose of the experiment and its functionality was tested. The depth of penetration of the drill into the test specimen was tested. The article describes the principle of measurement and the design of the initial experiment, but also the pitfalls, which had to be faced.

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AVALIAÇÃO DA EFICIÊNCIA DO HERBICIDA IMAZAPYR NA REDUÇÃO DA DEFORMAÇÃO RESIDUAL LONGITUDINAL EM Eucalyptus dunnii

FLORESTA ◽

10.5380/rf.v43i4.26139 ◽

2013 ◽

Vol 43 (4) ◽

pp. 549

Author(s):

Marcos Aurélio Mathias Souza ◽

Jorge Luis Monteiro de Matos ◽

Fernando Campanhã Bechara

Keyword(s):

Growth Stress ◽

Growth Strain ◽

Herbicide Application ◽

Second Stage ◽

Eucalyptus Dunnii ◽

Standing Trees ◽

Old Trees ◽

Two Stages ◽

Non Destructive ◽

Destructive Methods

Este trabalho avaliou a eficiência do herbicida Imazapyr (“Chopper”) na redução de tensões de crescimento em árvores de Eucalyptus dunnii Maiden. Foram testadas 20 árvores de 14 anos em Canoinhas, SC. Este trabalho foi subdivido em duas etapas: 1 (calibração) e 2 (execução). Em ambas, fixaram-se dois pinos no DAP das árvores, um pino distante 45 mm do outro (fixados na direção da grã), para indicar a intensidade da deformação residual longitudinal (DRL). Após a calibragem do aparelho, foi feito um furo de2 cm de diâmetro, com um arco de pua, entre os dois pinos, com o objetivo de liberar as tensões e registrar as deformações. As deformações foram medidas sob dois tratamentos – testemunha e com uso de Imazapyr – e comparadas através de análise de variância, em três momentos (1, 15 e 30 dias após a aplicação do herbicida). Apesar de os resultados preliminares (0,103 e 0,135 mm, com e sem herbicida, respectivamente) terem apontado que o herbicida foi, estatisticamente, eficiente na redução das tensões de crescimento em toretes, na etapa 2 as médias em árvores em pé com aplicação de herbicida das três medições (0,131, 0,127 e 0,127 mm) apresentaram apenas uma tendência de queda da DRL.Palavras-chave: Tensões de crescimento; metodologias não destrutivas; eucalipto. AbstractEvaluation of Imazapyr herbicide efficiency in reduction of longitudinal residual strain in Eucalyptus dunnii. This research evaluated the efficiency of the systemic herbicide Imazapyr ("Chopper") in reduction of growth stress of Eucalyptus dunnii Maiden trees. We tested twenty 14-year-old trees in Canoinhas-SC. This research was divided in two stages: 1 (calibration) and 2 (execution). In both, we fixed two pins in the trees DBH: one pin 45 mm apart from each other, aiming to release tensions and register deformations. We measured deformations in two treatments – control and with Imazapyr – and compared it by variance analysis in three moments (1, 15 and 30 days before the herbicide application). Even though the preliminary results (0.103 e 0.135 mm, with and without herbicide, respectively) pointed that the herbicide was, statistically, efficient in the reduction of growth tensions in short logs, in the second stage, the averages in standing trees with application of herbicide of the three measurements (0.131; 0.127; and 0.127 mm) presented only a tendency to decrease in DRL.Keywords: Growth strain; non-destructive methods; eucalyptus.

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