Potentials of the evaluation of the wood quality in living trees by using semi-and non-destructive methods in order to reduce wood-processing costs

2019 ◽  
pp. 115-126
Author(s):  
Ivana Živanović ◽  
Zoran Poduška ◽  
Ljubinko Rakonjac ◽  
Filip Jovanović
Keyword(s):  
Mechanical Properties ◽  
Wood Density ◽  
Bending Strength ◽  
Wood Quality ◽  
Renewable Resource ◽  
Relative Mass ◽  
Heterogeneous Structure ◽  
Wood Processing ◽  
Non Destructive ◽  
Destructive Methods

Being a natural, ecological and renewable resource, wood is increasingly replacing artificial and toxic materials in the manufacture of various types of packaging and other products; thus, its proper and economically justified use has become necessary. The best utilization of wood raw materials has been sought both in practice and theory, which led to the development of a number of non-destructive and semi-destructive methods for the wood quality assessments in various stages of wood exploitation. In this paper, two instruments for the inspection of the internal condition of standing trees were analyzed. The resistograph was designed for the detection of internal defects. In addition to assessing the condition of living trees of different species, the instrument is used to assess the wood density in various materials. The observed resistance during drilling is proportional to the change in the wood density or the relative mass of the element analyzed. The results of drilling in different spots or directions, through the cross-section and along the element, can be used to map the properties of the element. The fractometer is a device designed to measure the strength and other mechanical properties of on a core sample extracted by using an increment borer from a certain part of the tree or branch examined. The fractometer can determine the maximum fracture force and bending and pressure strength of wood. It is also possible to identify the stage of decay. Due to its heterogeneous structure and anisotropy, the wood compressive and bending strengths differ between different anatomical directions even within a single species. The results of previous research in the literature indicate that there is a significant positive correlation between the radial bending strength and the longitudinal compressive strength of wood. This actualizes the need for the use of different tree species in construction, depending on the load that the wood element will be exposed to. These devices provide high precision and quality in measurement and can achieve a good correlation between the measured values and the mechanical properties of wood. This way, science and practice could be provided by significant data on the properties and quality of wood, while its consumption is minimized.

scholarly journals Innovative methods of non-destructive evaluation of log quality

2021 ◽  
Vol 67 (1) ◽  
pp. 3-13
Author(s):  
Vojtěch Ondrejka ◽  
Tomáš Gergeľ ◽  
Tomáš Bucha ◽  
Michal Pástor
Keyword(s):  
Three Dimensional ◽  
Renewable Resource ◽  
Wood Properties ◽  
Raw Material ◽  
Production Flow ◽  
Visual Evaluation ◽  
Wood Processing ◽  
Pulp Paper ◽  
Non Destructive ◽  
Destructive Methods

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.

scholarly journals INVESTIGATION OF THE PHYSICAL-MECHANICAL PROPERTIES OF TIMBER USING ULTRASOUND EXAMINATION

2012 ◽  
Vol 18 (6) ◽  
pp. 795-801 ◽  
Author(s):  
Marko Teder ◽  
Kalle Pilt ◽  
Matis Miljan ◽  
Vello Pallav ◽  
Jaan Miljan
Keyword(s):  
Mechanical Properties ◽  
Modulus Of Elasticity ◽  
Bending Strength ◽  
Compressional Wave ◽  
Ultrasound Transducers ◽  
Indirect Measurements ◽  
Longitudinal Measurements ◽  
Direct Measurements ◽  
Strength And Stiffness ◽  
Non Destructive

This research uses a non-destructive method – ultrasound – to examine timber, combining the results of measurement with the properties of strength and stiffness. The purpose of this work is to explore the possibilities of grading wood structure in situ using ultrasound measurements, specifically, the moisture content and density of the timber. The timber used in these experiments was taken from existing buildings of different ages. The potential of replacing direct measurements with indirect measurements by ultrasound was also investigated. The physical-mechanical properties of wood were determined in laboratory conditions according to standard practices, and the method of non-destructive measurements was based on a commercial test device based on 54 kHz compressional wave 50 mm diameter ultrasound transducers. Direct measurements were performed in the longitudinal and radial material directions. Indirect measurements were performed with transducers positioned on the same lateral surface of the sample. A weak correlation was found with-in the different measurements. Longitudinal measurements characterise bending strength with R2 = 0.18 and modulus of elasticity with R2 = 0.37. In multiple regression analysis, stronger correlations were found; prediction equations of bending strength and modulus of elasticity were found with R2 = 0.40 and R2 = 0.81, respectively.

scholarly journals Wood Quality Characterization of Sycamore Maple (Acer pseudoplatanus L.) and its Utilization in Wood Products Industries

2021 ◽  
Vol 42 (3) ◽  
Author(s):  
Tomislav Sedlar ◽  
Bogoslav Šefc ◽  
Srđan Stojnić ◽  
Tomislav Sinković
Keyword(s):  
Mechanical Properties ◽  
Compression Strength ◽  
Modulus Of Elasticity ◽  
Bending Strength ◽  
Wood Quality ◽  
Beech Wood ◽  
Wood Products ◽  
Dry Density ◽  
Acer Pseudoplatanus ◽  
Sycamore Maple

This study quantified the physical and mechanical properties of sycamore maple (Acer pseudoplatanus L.) as a basis for assessing wood quality. The physical properties of oven-dry density, density at 12% MC, green density, basic density, longitudinal, radial, tangential and volumetric shrinkages were tested and the mechanical properties of bending strength, modulus of elasticity at bending, compression strength parallel to grain and compression strength in radial and tangential direction as well as of Brinell hardness on the cross, radial, and tangential section were determined. Five sycamore maple trees from Medvednica region were selected for the purposes of this research. The results were compared with known literature data on sycamore maple wood, beech wood from the same sight, and beech wood from Gorski Kotar region. For a better understanding of sycamore maple physiology, as well as for assessing the quality of wood products, the distribution of wood properties within the tree radius, from pith to bark, was investigated. There was a general bell shaped distribution, in the radial direction, in wood density, and mechanical properties of sycamore maple wood. Shrinkages decreased from pith to bark, except for tangential shrinkage with bell shaped pattern. All investigated wood densities of sycamore maple from Medvednica were similar to the findings of studies known in literature, as well as shrinkages, except for the lower longitudinal shrinkage. Investigated mechanical properties of sycamore maple wood were similar to the findings of studies known in literature, except for the lower bending strength and modulus of elasticity (MOE). Investigated sycamore maple indicated better dimensional stability than beech wood from two locations in the region, although it did not match the beech wood regarding mechanical properties, especially wood hardness.

scholarly journals DIAGNOSTICS OF THE PHYSICAL AND MECHANICAL PROPERTIES OF THE METAL BY THE PARAMETERS OF THE ELASTIC-PLASTIC INDENTATION OF A SPHERICAL INDENTER

2020 ◽  
pp. 58-62
Author(s):  
M. M. Matlin ◽  
V. A. Kazankin ◽  
E. N. Kazankina
Keyword(s):  
Mechanical Properties ◽  
Physical And Mechanical Properties ◽  
Spherical Indenter ◽  
Test Material ◽  
Tensile Stresses ◽  
Elastic Plastic ◽  
Plastic Indentation ◽  
Non Destructive ◽  
Destructive Methods

The paper describes non-destructive methods for determining the physical and mechanical properties of metals based on the regularities of elastic-plastic indentation of a spherical indenter into the test material. Using the proposed methods makes it possible to construct a diagram of true tensile stresses based on the results of a single indentation of a spherical indenter.

Assessment of the effect of defects on mechanical properties of adhesive bonded joints by using non destructive methods

2016 ◽  
Vol 91 ◽  
pp. 337-345 ◽  
Author(s):  
Rosanna Tamborrino ◽  
Davide Palumbo ◽  
Umberto Galietti ◽  
Patrizia Aversa ◽  
Samanta Chiozzi ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Bonded Joints ◽  
Adhesive Bonded Joints ◽  
Non Destructive ◽  
Destructive Methods

Study and Evaluation on Physical and Mechanical Properties of 40 Kinds of Wood Species in Zhejiang Province (China)

2014 ◽  
Vol 962-965 ◽  
pp. 657-662
Author(s):  
Man Ping Xu ◽  
Fei Yan Guo ◽  
Kan Kan Zhou ◽  
Wei Ming Yang
Keyword(s):  
Mechanical Properties ◽  
Wood Species ◽  
Bending Strength ◽  
Comprehensive Evaluation ◽  
Physical And Mechanical Properties ◽  
Zhejiang Province ◽  
Modulus Of Rupture ◽  
Processing Application ◽  
Wood Processing ◽  
Analysis Methods

Physical and mechanical properties of 40 kinds of typical wood species in Zhejiang province were studied in this experiment. Density, shrinkage rate, modulus of rupture,bending strength, compression strength, shear strength and hardness were measured and wood species were classified and evaluated by clustering analysis mehtod (CA) combined with membership function (MF) comprehensive evaluation according to these properties. The results showed that the two analysis methods achieved the similar results when screening first class wood which can be conclued that among the 40 kinds of species Quercus fabri, Dalbergia hupeana Cyclobalanopsis glauca, Lithocarpus harlandii and Lagerstroemia indica were the excellent quality. In the mean while the two analysis methods got the similar conclusion that wood properties of Pterocarya stenoptera were the worest as well. In addation, Camptotheca acuminata and Alniphyllum fortune according to CA and Ilex rotunda, and Cyclocarya paliurus according to MF were also the worest qulaity. The study provided powerful references for wood processing, application and directional cultivation of indigenous tree species in Zhejiang.

scholarly journals Functionality of Beech Bark in Adhesive Mixtures Used in Plywood and Its Effect on the Stability Associated with Material Systems

Materials ◽  
2019 ◽  
Vol 12 (8) ◽  
pp. 1298 ◽  
Author(s):  
Roman Réh ◽  
Rastislav Igaz ◽  
Ľuboš Krišťák ◽  
Ivan Ružiak ◽  
Milada Gajtanska ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Bending Strength ◽  
Urea Formaldehyde ◽  
Wood Processing ◽  
Material Systems ◽  
Adhesive Mixtures ◽  
The Common ◽  
The Stability ◽  
Heating Up

The results of research into utilizing grinded beech bark in order to substitute commonly used fillers in urea formaldehyde (UF) adhesive mixtures to bond plywood are presented in the present study. Four test groups of plywood with various adhesive mixtures were manufactured under laboratory conditions and used for experimentation. Plywood made using the same technology, with the common filler (technical flour), was used as a reference material. Three different concentrations of grinded beech bark were used. The thermal conductivity of the fillers used, viscosity and its time dependence, homogeneity and the dispersion performance of fillers were evaluated in the analysis of adhesive mixture. The time necessary for heating up the material during the pressing process was a further tested parameter. The produced plywood was analyzed in terms of its modulus of elasticity, bending strength, perpendicular tensile strength and free formaldehyde emissions. Following the research results, beech bark can be characterized as an ecologically friendly alternative to technical flour, shortening the time of pressing by up to 27%. At the same time, in terms of the statistics, the mechanical properties and stability of the material changed insignificantly, and the formaldehyde emissions reduced significantly, by up to 74%. The utilization of bark was in compliance with long-term sustainability, resulting in a decrease in the environmental impact of waste generated during the wood processing.

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