Predicting mechanical properties of clear wood from Acacia mangium provenances using ultrasound

Ultrasound was considered as a means for determining mechanical properties of clear wood in six different Acacia mangium provenances from a trial forest planted in Vietnam. A total of 30 trees (5 trees from each provenance) with no major defects were selected, and a 50-cm-long log was obtained at 1.3 m above the ground from each tree for the assessment of mechanical properties. The measured average ultrasound velocities for provenances tested in the longitudinal direction ranged from 4094 m/s to 4271 m/s. The predicted average dynamic modulus of elasticity (Ed) values varied from 7.42 GPa to 8.70 GPa among provenances. The Ed indicated significant positive correlation coefficients with modulus of elasticity (0.64 to 0.96), modulus of rupture (0.44 to 0.87), and compression strength (0.54 to 0.92) for provenances examined in this study. The results indicated that the use of ultrasound was feasible to determine the mechanical properties of A. mangium provenances planted in Vietnam.

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Prediction of Mechanical Properties of Hardwood Species Using the Longitudinal Vibration Acoustic Method

Forest Products Journal ◽

10.13073/fpj-d-21-00048 ◽

2021 ◽

Vol 71 (4) ◽

pp. 391-400

Author(s):

Kayode Olaoye ◽

Lawrence Aguda ◽

Bolade Ogunleye

Keyword(s):

Mechanical Properties ◽

Modulus Of Elasticity ◽

Dynamic Modulus ◽

Longitudinal Vibration ◽

Modulus Of Rupture ◽

Damping Factor ◽

Acoustic Parameters ◽

Static Modulus ◽

Hardwood Species ◽

Static Modulus Of Elasticity

Abstract Acoustic test methods such as longitudinal vibration have been developed to predict the elastic properties of wood. However, attention has not been shifted to using this method to predict other mechanical properties, especially on Nigeria's preferred, and lesser-used wood species. Thus, we further investigate relationships among mechanical and acoustic properties of selected hardwood species with a view of predicting the mechanical properties of wood from acoustic parameters. Clear wood samples (324) of 20 by 20 by 20 mm3 were collected axially from Albizia adianthifolia, Gmelina arborea, Delonix regia, and Boscia anguistifolia trees, and conditioned before testing. The longitudinal vibration method was adopted to test for the dynamic (acoustic) parameters and properties (fundamental frequency, damping factor, dynamic modulus of elasticity, sound velocity, specific elastic modulus, radiation coefficient, acoustic conversion efficiency, acoustic impedance) while the universal testing machine was used to test for the mechanical properties (static modulus of elasticity, modulus of rupture, maximum compression strength parallel to grain). The damping factor, dynamic modulus of elasticity, and acoustic impedance were the best acoustic parameters that significantly correlated with the static modulus of elasticity (−0.57, 0.81, 0.76), modulus of rupture −0.64, 0.82, 0.85) and maximum compression strength parallel to grain (−0.52, 0.78, 0.84), respectively. There was a significant difference in the mechanical properties with respect to species, thus A. adianthifolia and G. arborea were mechanically better than D. regia and B. anguistifolia for construction or structural purposes. This study revealed that additional new acoustic measures are suitable for inferring mechanical wood properties.

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Compression strength and other mechanical properties of particleboards induced by density

Annals of WULS, Forestry and Wood Technology ◽

10.5604/01.3001.0014.4413 ◽

2020 ◽

Vol 110 ◽

pp. 79-91

Author(s):

Aleksandra Jeżo ◽

Grzegorz Kowaluk

Keyword(s):

Mechanical Properties ◽

Density Profile ◽

Surface Finish ◽

Compression Strength ◽

Modulus Of Elasticity ◽

Physical Characteristics ◽

Modulus Of Rupture

Compression strength and other mechanical properties of particleboards induced by density. The aim of the paper was to investigate the contractual compression strength and modulus of elasticity under compression of six types of commercially available particleboards of various thickness, density and surface finish. The basic mechanical and physical characteristics of the tested panels (modulus of elasticity and modulus of rupture during bending, density and density profile) were also performed. The studies showed that the compression strength raises linearly with panels’ density raise, and the modulus of elasticity under compression is linearly opposite, depending on the panels’ density.

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Pengaruh Tekanan dan Penggunaan Conplast terhadap Sifat Mekanik Eternit dari Abu Cangkang Sawit

Jurnal Riset Teknologi Industri ◽

10.26578/jrti.v8i15.1552 ◽

2016 ◽

Vol 8 (15) ◽

pp. 47-54

Author(s):

Haspiadi Haspiadi

Keyword(s):

Mechanical Properties ◽

Oil Palm ◽

Modulus Of Elasticity ◽

Modulus Of Rupture ◽

Palm Shell ◽

Oil Palm Shell ◽

Density Values ◽

Test Result

The purpose of this research is to know the influence of pressure and use of conplast against mechanical properties which are a Modulus of Elasticity (MOE) and Modulus of Rupture (MOR) of plasterboard. The study is done because still low quality of plasterboard made from a mixture of ashes of oil-palm shell especially of the mechanical properties compared to the controls. The method of this reserach used variation of printed pressure and the addition of conplast. Test result is obtained that the highest value of Modulus of Elasticity (MOE) 90875.94 Kg/cm2, Modulus of Rupture (MOR) 61.16 Kg/cm2 and density values in generally good printed at the pressure 60 g/cm3 and the addition of conplast 25% as well as the composition of the ash of palm shell oil 40%: limestone 40%: cement 15%: fiber 5% and 300 mL of water. ABSTRAK Tujuan dari penelitian ini adalah untuk mengetahui pengaruh tekanan dan penggunaan conplast terhadap sifat mekanik yaitu kuat lentur dan keteguhan patah eternit berbahan dasar abu cangkang sawit. Penelitian ini dilakukan karena masi rendahnya mutu eternit berbahan campuran abu cangkang sawit dari bolier khususnya sifat mekanik dibandingkan dengan kontrol. Metode penelitian yang digunakan adalah dengan variasi tekanan cetak dan penambahan conplast. Hasil uji diperoleh bahwa kuat lentur tertinggi sebesar 90875,94 Kg/cm2 dan keteguhan patah sebesar 61,16 Kg/cm2, yang dicetak pada tekanan 60 g/cm3 dan penambahan conplast 25% dengan komposisi abu cangkang sawit 40 %: kapur 40 % : semen 15 %: serat 5 % dan air 300 mL.Kata Kunci : Abu cangkang sawit, conplast, kuat lentur, keteguhan patah.

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ANALYSIS OF SOUND SPEED IN LONGITUDINAL DIRECTION AT REFERENCE MOISTURE CONTENT (w = 12 %) IN SAWMILL ASSORTMENTS (FAGUS SYLVATICA, L.)

Akustika ◽

10.36336/akustika20203745 ◽

2020 ◽

pp. 45-50

Author(s):

Alena Rohanová

Keyword(s):

Moisture Content ◽

Modulus Of Elasticity ◽

Dynamic Modulus ◽

Sound Speed ◽

Longitudinal Direction ◽

Structural Timber ◽

Sound Speeds ◽

Dynamic Modulus Of Elasticity ◽

Round Timber

This paper explores the analysis of sound speeds in the longitudinal direction and their reduction to the reference moisture content w = 12 %. The sound speed cw was determined with Sylvatest Duo device. Moisture content of beech sawmill assortments (round timber: N = 16, logs: N = 2 × 16, structural boards: N = 54) in the range of 12 – 72 % was measured. For the analysis purposes, the sound speed was converted to reference conditions (c12, uref = 12%). A second-degree polynomial (parabola) with a regression equation of the form: c// = 5649 - 27,371 × w + 0.0735 × w2 was used to convert cw to c12, and correction of measured and calculated values was used as well. The sound speeds c12 in sawmill assortments (c12,round, c12,log, c12,board) were evaluated by linear dependences. Dependence was not confirmed for c12,round and c12,board1 (r = 0.168), in contrast for c12,round and c12,log2 the dependence is statistically very significant (r = 0.634). The results of testing showed that the most suitable procedure for predicting quality of structural timber is the first step round timber – log2, the second step: log2 - board2. More exact results of the construction boards were obtained from log2 than from log1. The sound speed is used in the calculation of dynamic modulus of elasticity (Edyn). EN 408 mentions the possibility of using dynamic modulus of elasticity as an alternative method in predicting the quality of structural timber.

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Influence of Moisture Content in some Mechanical Properties of Two Brazilian Tropical Wood Species

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1025-1026.42 ◽

2014 ◽

Vol 1025-1026 ◽

pp. 42-45 ◽

Cited By ~ 1

Author(s):

Luiz A. Melgaço N. Branco ◽

Eduardo Chahud ◽

André Luis Christoforo ◽

Francisco Antonio Rocco Lahr ◽

Rosane A.G. Battistelle ◽

...

Keyword(s):

Mechanical Properties ◽

Shear Strength ◽

Moisture Content ◽

Analysis Of Variance ◽

Wood Species ◽

Modulus Of Elasticity ◽

Modulus Of Rupture ◽

Tropical Wood ◽

Fiber Saturation ◽

Brazilian Standard

This study aimed, with the aid of analysis of variance (ANOVA), to investigate and quantify the influence of moisture ranging between 12% and over 30% (fiber saturation) on the mechanical properties: strength and modulus of elasticity in compression and in tension parallel to grain; modulus of rupture and modulus of elasticity in static bending; shear strength parallel to grain considering wood species Ipê (Tabebuia sp) and Angelim Araroba (Vataireopsis araroba). Tests were performed according to the assumptions and calculating methods Brazilian standard ABNT NBR 7190, Anexx B, totalizing 400 tests. Results of ANOVA revealed a significant reduction (16% on average) for mechanical properties wood due to the increase in moisture content from 12% to over 30% (fiber saturation). The same behavior also occurred when assembly containing the two species was considered.

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Sixteen properties of Eucalyptus Tereticornis wood for structural uses

Bioscience Journal ◽

10.14393/bj-v36n2a2020-45169 ◽

2020 ◽

Vol 36 (2) ◽

Cited By ~ 2

Author(s):

Marta Cristina de Jesus Albuquerque Nogueira ◽

Victor Almeida de Araujo ◽

Juliano Souza Vasconcelos ◽

André Luis Christoforo ◽

Francisco Antonio Rocco Lahr

Keyword(s):

Mechanical Properties ◽

Decision Making ◽

Shear Stress ◽

Modulus Of Elasticity ◽

Strength Properties ◽

Modulus Of Rupture ◽

Eucalyptus Tereticornis ◽

Moisture Contents ◽

Through Diffusion ◽

Standard Documents

Forest Red Gum eucalypt provides a versatile wood and is converted into different purposes. However, such wood is somewhat limited in structural ends, which highlights the need to exploit this gap through diffusion of mechanical properties of such timber. Obtained results should assist engineers and architects in decision-making for its best building application. This paper studied two physical and fourteen mechanical properties evaluation of Eucalyptus tereticornis at two different moisture contents, following the prescriptions of Brazilian (ABNT NBR 7190: 1997) and North American (ASTM D-143-14: 2014) standard documents. Thus, 1091 repeats were carried out for all properties. By a moisture reduction from 30% to 12%, the bulk density and eleven strength properties statistically showed changes such as modulus of rupture (static bending, parallel and perpendicular compressions), modulus of elasticity (perpendicular compression and static bending), shear stress, tangential cleavage, and parallel and perpendicular hardnesses. Then, the Eucalyptus tereticornis timber could be better usable if is further applied for structural construction uses.

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Mechanical Properties of Commercial Particleboard from Rubberwood (Hevea Brasiliensis) and Recycle Mix-Tropical Wood with Different Board Density

Science Proceedings Series ◽

10.31580/sps.v3i1.1941 ◽

2021 ◽

Vol 3 (1) ◽

pp. 41-44

Author(s):

Nur Wafa Amalina Amali ◽

Nor Yuziah Mohd Yunus ◽

Wan Mohd Nazri Wan Abdul Rahman

Keyword(s):

Mechanical Properties ◽

Modulus Of Elasticity ◽

Hevea Brasiliensis ◽

Urea Formaldehyde ◽

Wood Particle ◽

Modulus Of Rupture ◽

Internal Bonding ◽

Board Density ◽

Tropical Wood ◽

Minimum Requirements

In this study, mechanical properties of commercially manufactured hybrid particleboard from mix-tropical wood and rubberwood with four different densities at 25mm thickness have been investigated. The particleboard sample cutting and testing was in accordance to EN312:2013. The density of particleboard is identified with interval of 10kg/m3 for different densities which include 660kg/m3, 670kg/m3, 680kg/m3 and 690kg/m3. Particleboards were made with the ratio of 40:60 for mix-tropical wood particle and rubberwood particle respectively. The particleboards were prepared with urea formaldehyde (UF) with E1 formulation with addition of wax and hardener. Increment of 10kg/m3 density for each particleboard led to increase in internal bonding (IB), bending testing include modulus of rupture (MOR) and modulus of elasticity (MOE), surface soundness (SS) and screw edge (SE) withdrawal. It was found that with board increment of 10kg/m3, the improvement was not statically significant except that for MOR. All panels met the minimum requirements of standard.

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Design and Property Analysis of the Metal Mesh Reinforced LVL

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.113-116.2145 ◽

2010 ◽

Vol 113-116 ◽

pp. 2145-2149

Author(s):

Ying Cheng Hu ◽

Jin Li ◽

Fang Chao Cheng ◽

Xu Jie Zhang

Keyword(s):

Mechanical Properties ◽

Modulus Of Elasticity ◽

Modulus Of Rupture ◽

Bending Test ◽

Metal Mesh ◽

Fast Growing ◽

Laminated Veneer Lumber ◽

Property Analysis ◽

Wood Grain

This study mainly analyzed the factors that affected the mechanical properties of laminated veneer lumber（LVL）. To increase the mechanical properties, metal mesh was inserted into LVL that made of fast-growing timber. Effects of different factors were evaluated on the mechanical properties of LVL, several enhancement modes of metal mesh were designed to reinforce the LVL. Then, the mechanical properties (modulus of rupture and modulus of elasticity) of the LVL specimens were measured by static bending test. The results of different enhancement modes were analyzed and compared to investigate the effects of different factors. The position of metal mesh and the mesh number of metal mesh make significant effects on the MOE; the type of metal mesh and the angle of metal mesh-wood grain do not have any obvious effects on the MOE. The type of metal mesh and the position of metal mesh make significant effects on the MOR; the mesh number of metal mesh and the angle of metal mesh-wood grain do not have any obvious effects on the MOR.

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The Effect of Impregnation Process on the Performance of Veneer Composite Plank

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.239-242.2411 ◽

2011 ◽

Vol 239-242 ◽

pp. 2411-2414

Author(s):

Xing Zhen ◽

Jiu Yin Pang ◽

Shi Cheng Zhang ◽

Ya Zhe Jiang

Keyword(s):

Mechanical Properties ◽

Drug Absorption ◽

Modulus Of Elasticity ◽

Absorption Rate ◽

Normal Pressure ◽

Modulus Of Rupture ◽

Impregnation Process ◽

Impregnation Time ◽

Peak Value

This study focuses on the effect of impregnation process on the main mechanical properties in the production of veneer composite plank. The results showed that:①Under the normal pressure and temperature the drug absorption of impregnated veneer shall extend the volume with the growth in impregnation time, but growing faster early, the later change slowly. In the impregnation process under pressure, its absorption rate and speed are greatly increased. ②The Modulus of rupture (MOR) and modulus of elasticity (MOE) of veneer composite plank are gradually increased with the drug absorption increased, but after reached a certain peak value they gradually decrease, and the variation of MOE is smaller than MOR.

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