scholarly journals The Behavior of Strength Properties from Three Different Tree Boles of Aras in Sarawak

2011 ◽  
Vol 2 (2) ◽  
pp. 48-52
Author(s):  
Gaddafi Ismaili ◽  
Badorul Hisham Abu Bakar ◽  
Khairul Khuzaimah Abdul Rahim
Keyword(s):  
Moisture Content ◽  
Physical Properties ◽  
Compressive Stress ◽  
Modulus Of Elasticity ◽  
Basic Density ◽  
Strength Properties ◽  
Modulus Of Rupture ◽  
Compression Stress ◽  
Mean Values ◽  
Green Condition

 Aras had been selected and tested in small clear specimens. Sampling of test specimens are made from three sections of the tree bole namely from bottom, middle, and top parts. This paper looks into the information of strength properties from three sections of sampled. The strength properties test required are the modulus of rupture, modulus of elasticity and compression stress parallel to grain. Meanwhile, the physical properties' test referred to moisture content and basic density. The testing conducted in two different conditions of the trees, which were referred to green and air-dry condition. It was found that the average mean values for modulus of rupture, modulus of elasticity and compressive stress parallel to grain tested at green condition were 47.52N/mm2, 6358.56N/mm2 and 22.42N/mm2 respectively meanwhile at air-dry condition were 70.49N/mm2, 8217.64N/mm2 and 34.07N/mm2 respectively. Meanwhile, the average mean values for moisture content at green condition were 83.34% whilst at the air-dry condition were 12.33%. Basic density remains unchanged from both conditions.

scholarly journals Evaluation of Acacia Mangium in Structural Size at Green Condition

2011 ◽  
Vol 2 (2) ◽  
pp. 17-22 ◽  
Author(s):  
Gaddafi Ismaili ◽  
Badorul Hisham Abu Bakar ◽  
Khairul Khuzaimah Abdul Rahim
Keyword(s):  
Tensile Strength ◽  
Moisture Content ◽  
Mechanical Strength ◽  
Physical Properties ◽  
Basic Density ◽  
Acacia Mangium ◽  
Strength Properties ◽  
Modulus Of Rupture ◽  
Structural Size ◽  
Green Condition

Acacia mangium is one of the most popular choices in the reforestation and rehabilitation of abandoned shifting cultivation areas dated back to the 70’s. This paper looks into the evaluation of mechanical strength and physical properties in structural size at green condition for Acacia mangium. The mechanical strength properties tests were referred to the modulus of rupture, modulus of elasticity and tensile strength. Meanwhile, physical properties determination referred to basic density and moisture content. At green condition, Acacia mangium had been identified under the strength group SG6. It was found that strength value of modulus of rupture was higher than the tensile strength value with 44% stronger in bending compared to in tension. At the structural size, the mean value for moisture content and basic density at green condition were reported with 73.03% and 0.54g/cm3 respectively.

Mechanical properties of Ficus vallis-choudae (Delile), a lesser utilized species in Nigeria

BioResources ◽  
2020 ◽  
Vol 15 (3) ◽  
pp. 6550-6560
Author(s):  
Lawrence Aguda ◽  
Babatunde Ajayi ◽  
Sylvester Areghan ◽  
Yetunde Olayiwola ◽  
Aina Kehinde ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Shear Strength ◽  
Moisture Content ◽  
Modulus Of Elasticity ◽  
Bending Strength ◽  
High Strength ◽  
Strength Properties ◽  
Modulus Of Rupture ◽  
Impact Bending ◽  
Timber Market

Declining availability of the prime economic species in the Nigerian timber market has led to the introduction of Lesser-Used Species (LUS) as alternatives. Their acceptability demands information on the technical properties of their wood. The aim of this study was to investigate the mechanical properties of Ficus vallis-choudae to determine its potential for timber. Three mature Ficus vallis-choudae trees were selected and harvested from a free forest area in Ibadan, Oyo State, Nigeria. Samples were collected from the base (10%), middle (50%), and top (90%) along the sampling heights of each tree, which was further partitioned into innerwood, centrewood, and outerwood across the sampling radial position. Investigations were carried out to determine the age, density, moisture content, impact strength, modulus of elasticity, modulus of rupture, compressive strength parallel-to-grain, and shear strength parallel-to-grain. The mean impact bending strength, modulus of rupture, modulus of elasticity, maximum shear strength parallel-to-grain, and maximum compression strength parallel-to-grain for Ficus vallis-choudae at 12% moisture content were 20.4 N/mm2, 85.8 N/mm2, 709 N/mm2, 10.7 N/mm2, and 33.6 N/mm2, respectively. The study found the species to be dense with high strength properties in comparison with well-known timbers used for constructional purposes.

Physical properties and compression loading behaviour of corn seed

2013 ◽  
Vol 27 (2) ◽  
pp. 119-126 ◽  
Author(s):  
Lj. Babić ◽  
M. Radojèin ◽  
I. Pavkov ◽  
M. Babić ◽  
J. Turan ◽  
...  
Keyword(s):  
Moisture Content ◽  
Physical Properties ◽  
Modulus Of Elasticity ◽  
Compressive Loading ◽  
Secant Modulus ◽  
Seed Moisture Content ◽  
Mean Values ◽  
Compression Loading ◽  
Corn Seed ◽  
Dent Corn

Abstract The aim of this study was to acquire data on the physical properties and compression loading behaviour of seed of six corn hybrid varieties. The mean values of length, width, thickness, geometric diameter, surface area, porosity, single kernel mass, sphericity, bulk and true density, 1 000 kernelmass and coefficient of friction were studied at single level of corn seed moisture content. The calculated secant modulus of elasticity during compressive loading for dent corn was 0.995 times that of the semi-flint type; there were no significant differences in the value of this mechanical property between semi-flint and dent corn varieties. The linear model showed a decreasing tendency of secant modulus of elasticity for all hybrids as the moisture content of seeds increased.

scholarly journals Kualitas Pengeringan Kayu Mahoni Pada Berbagai Variasi Kerapatan Incising Dengan Dua Skedul Pengeringan Suhu tinggi

2016 ◽  
Vol 10 (2) ◽  
pp. 119
Author(s):  
Tomy Listyanto ◽  
Fadlul Rahman ◽  
Hyana Swargarini
Keyword(s):  
Moisture Content ◽  
Modulus Of Elasticity ◽  
Strength Properties ◽  
Small Sample ◽  
Moisture Distribution ◽  
Modulus Of Rupture ◽  
Bending Test ◽  
Drying Rate ◽  
Measure Moisture Content ◽  
Moisture Content Distribution

Tujuan dari penelitian ini adalah untuk mengetahui pengaruh interaksi variasi kerapatan incising dan dua skedul pengeringan terhadap kecepatan dan cacat-cacat pengeringan kayu mahoni, serta mengetahui pengaruh variasi kerapatan incising terhadap kekuatan lengkung statik kayu mahoni yang telah dikeringkan. Tiga pohon mahoni (Swietenia mahagony) berdiameter 300-350 mm ditebang dan selanjutnya dibelah dan dibuat menjadi balok dengan ukuran 60 mm × 100 mm dengan panjang 500 mm untuk dijadikan sampel pengeringan. Di antara masing-masing bagian tersebut, dibuat sampel ukuran 20 mm × 20 mm × 25 mm, yang digunakan untuk penentu kadar air awal dan distribusinya. Sampel pengeringan selanjutnya dibagi menjadi 5 variasi kerapatan incising, yaitu 0 lubang/m2 (tanpa incising), 1000 lubang/m2, 2000 lubang/m2, 3000 lubang/m2, dan 4000 lubang/m2. Setiap variasi kerapatan incising selanjutnya akan dikeringkan dengan 2 skedul pengeringan, yaitu suhu pengeringan 100°C sampai tercapai kadar air akhir 12% dan suhu 60°C pada 8 jam pertama dan selanjutnya dilanjutkan 100°C, sampai tercapai kadar air akhir 12%. Paramater yang diamati adalah kecepatan pengeringan, cacat retak permukaan, dan distribusi kadar air akhir. Hasil analisis menunjukkan bahwa kerapatan incising 3000-4000 lubang/m2 memberikan pengaruh yang cukup nyata di dalam mempercepat proses pengeringan dan distribusi kadar air akhir. Skedul pengeringan dan variasi kerapatan incising tidak berpengaruh pada retak permukaan. Pra perlakuan incising sampai batas 4000 lubang/m2 ini dapat diterapkan untuk mempercepat proses pengeringan dengan penurunan nilai modulus elastisitas dan modulus patah yang tidak berbeda nyata.Kata kunci: incising, pengeringan suhu tinggi, mahoni, lengkung statik, skedul pengeringan AbstractThe aims of this research were to investigate the effects of interaction between incising densities and two drying schedules on drying rate and defects as well as to examine the effect of incising densities on static bending characteristics of dried mahogany. Tree mahogany (Swietenia mahogany) trees with the diameter of 300-350 mm were cut and sawn into columns with the dimension of 60 mm ×100 mm × 500 mm. Each column was cut into five parts with the length of 500 mm. A small sample with the dimension of 20 mm × 20 mm × 25 mm were taken in between drying sample to measure moisture content. Five incising densities, which were 0 holes/m2 (unincised), 1000 holes/m2, 2000 holes/m2, 3000 holes/m2 and holes/m2, were applied to the drying sample. Samples were dried with two different drying schedules until the moisture content of 12%. Drying rate, defects, and moisture distribution were measured to evaluate the drying quality. Static bending test was applied to examine the strength properties. The results showed that incising densities of 3000-4000 holes/m2 could significantly improve drying rate and final moisture content distribution. There was no significants defects due to the variation of incising densities and drying schedules. No significant decrease of modulus of elasticity and modulus of rupture among five incising densities was found in this research.

Medium Density Particleboard with Addition of Impregnated Paper

2014 ◽  
Vol 1025-1026 ◽  
pp. 543-546
Author(s):  
Juliana Cortez Barbosa ◽  
Anderson Luiz da Silva Michelon ◽  
Elen Aparecida Martines Morales ◽  
Cristiane Inácio de Campos ◽  
André Luis Christoforo ◽  
...  
Keyword(s):  
Moisture Content ◽  
Modulus Of Elasticity ◽  
Mechanical Tests ◽  
Modulus Of Rupture ◽  
Medium Density ◽  
Test Results ◽  
Thickness Swelling ◽  
Adhesion Test ◽  
Layer Medium ◽  
Determine Moisture Content

The aim of this research was to produce three-layer Medium Density Particleboard (MDP), with the addition of impregnated paper, in the inner layer, in proportions of 1; 5 and 20%. In this study, MDP was composed with particles of small size in outer layers, and larger particles in internal layer. After panel manufacturing, physical and mechanical tests based on Brazilian Code ABNT NBR 14.810 were carried out to determine moisture content; density; thickness swelling; water absorption; modulus of rupture (MOR) and modulus of elasticity (MOE) in static bending and internal adhesion. Test results were compared to commercial panels, produced with 100% Eucalyptus, considering the requirements specified by Brazilian Code. Properties presented values close to normative specifications, indicating positively the possibility of production of MDP using addition of waste paper impregnated.

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

2014 ◽  
Vol 1025-1026 ◽  
pp. 42-45 ◽  
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.

scholarly journals Basic and Grade Stress for Some Timber in Sarawak

2011 ◽  
Vol 2 (2) ◽  
pp. 35-38
Author(s):  
Gaddafi Ismaili ◽  
Badorul Hisham Abu Bakar ◽  
Khairul Khuzaimah Abdul Rahim
Keyword(s):  
Exotic Species ◽  
Modulus Of Elasticity ◽  
Acacia Mangium ◽  
Wood Properties ◽  
Strength Properties ◽  
Indigenous Species ◽  
Medium Density ◽  
Compression Stress ◽  
Strength Group ◽  
Fast Growing Species

Strength properties’ tests are conducted in the small clear sample. This paper aim to acquire the basic and grade stresses of some fast growing species thus identifies its strength group. Thus, the information of wood properties from different species and condition are acquired from strength property's test. The required information namely, bending parallel to the grain, compression stress parallel to grain, shear parallel to grain and modulus of elasticity. The condition of the trees which is referred to green and air-dry condition. Three different species which are referred to exotic species of Acacia mangium and indigenous species of Aras. The results from the study indicated that, Acacia mangium classified under the strength group SG5, whilst Aras was classified under the strength group SG7. The timber is of medium density Light Hardwood ranging from 0.37-0.52g/cm3 air-dry condition.

scholarly journals Sixteen properties of Eucalyptus Tereticornis wood for structural uses

2020 ◽  
Vol 36 (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.

Effect of juvenile wood on strength properties and dimensional stability of black spruce medium-density fiberboard panels

Holzforschung ◽  
2005 ◽  
Vol 59 (1) ◽  
pp. 1-9 ◽  
Author(s):  
Jun Li Shi ◽  
Shu Yin Zhang ◽  
Bernard Riedl
Keyword(s):  
Water Absorption ◽  
Dimensional Stability ◽  
Juvenile Wood ◽  
Black Spruce ◽  
Medium Density Fiberboard ◽  
Strength Properties ◽  
Analysis Of Covariance ◽  
Modulus Of Rupture ◽  
Medium Density ◽  
Mean Values

Abstract Strength properties and dimensional stability of medium-density fiberboard (MDF) panels made from black spruce (Picea mariana [Mill.] BSP.) 0–20, 21–40, and over 40 year old fiber were studied. An analysis of covariance (ANCOVA) was performed to examine the differences in modulus of rupture (MOR), modulus of elasticity (MOE), and thickness swell (TS) of the three types of panels, while panel density was treated as a covariate in order to adjust the mean values that were partly attributed to panel density. The results indicate that MOR, internal bond (IB), and water absorption of MDF panels made from 0–20 year old fiber, which contained 100% juvenile wood, were significantly superior to those of panels made from 21–40 and over 40 year old fiber; but linear expansion (LE) of MDF panels made from 0–20 year old fiber was significantly larger than that of panels from the other two age classes. The differences in MOR, IB, water absorption, and LE between panels made from 21–40 and over 40 year old fiber were not significant. The comparisons of panel MOE and TS were relatively dependent on panel density due to existence of interactions among the three age groups.

Effect of Particle Size on Some Properties of Rice Husk Particleboard

2007 ◽  
Vol 18-19 ◽  
pp. 43-48 ◽  
Author(s):  
J.O. Osarenmwinda ◽  
J.C. Nwachukwu
Keyword(s):  
Particle Size ◽  
Physical Properties ◽  
Water Absorption ◽  
Rice Husk ◽  
Modulus Of Elasticity ◽  
Internal Bond ◽  
Elasticity Modulus ◽  
Modulus Of Rupture ◽  
Thickness Swelling ◽  
Effect Of Particle Size

The purpose of this study was to determine the effect of particle size on the mechanical properties (Modulus of Elasticity, Modulus of Rupture, and Internal Bond) and physical properties (thickness swelling and water absorption) of rice husk particleboard. The particle sizes used were 1.0mm, 1.18mm, 2mm, 2.36mm and 2.80mm. Each was mixed with a constant resin (urea formaldehyde) concentration of 20% of oven dry weight of rice husk particles. The results showed that as the particle size increased, the particleboard’s mechanical and physical properties decreased. For example, the modulus of elasticity, modulus of rupture, internal bond, thickness swelling and water absorption for 1.0mm particle size particleboard were 1590N/mm2, 11.11N/mm2, 0.28N/mm2,10.90% and 38.53% respectively, while for 2.8mm particle size they were 1958N/mm2,14.2N/mm2, 0.44N/mm2, 11.51% and 47.21% respectively. Overall results showed that particleboard made from rice husk exceed the EN standard for modulus of elasticity, modulus of rupture, internal bond. However, thickness swelling values were poor. Hence, the smaller the particle size the better the properties of the particleboard.

Sign in / Sign up

Export Citation Format

Share Document