How Variability in OSB Mechanical Properties Affects Biological Durability Testing

Holzforschung ◽  
2003 ◽  
Vol 57 (1) ◽  
pp. 8-12
Author(s):  
S. F. Curling ◽  
J. E. Winandy ◽  
C. Carll ◽  
J. A. Micales ◽  
A. A. Tenwolde
Keyword(s):  
Mechanical Properties ◽  
Bending Strength ◽  
Particle Orientation ◽  
Modulus Of Rupture ◽  
Simple Method ◽  
Oriented Strandboard ◽  
Two Samples ◽  
Durability Testing ◽  
Biological Durability ◽  
Tensile Surface

Summary Loss in bending strength of wood has been shown to be a more sensitive measure of decay than is weight loss. Using modulus of rupture as the decay criterion is problematic for oriented strandboard (OSB) because of variation in mechanical properties due to particle orientation and size. Moreover, the small specimen size required for such tests increases the variance in mechanical properties. This study compared the variance in bending strength of ASTM D1037 standard-sized specimens and small specimens from two samples of commercial OSB. The small specimens were found to have a significantly higher level of variance in bending strength than the standard-sized specimens. A simple method of sorting the specimens based on strand orientation on the tensile surface significantly reduced the level of variance measured. The effects of differing levels of variance on the size, design and limitations of the experimental study are presented.

scholarly journals Near infrared spectroscopy for assessing mechanical properties of Castanea sativa wood samples

2019 ◽  
Vol 50 (4) ◽  
pp. 191-197 ◽  
Author(s):  
Manuela Mancini ◽  
Elena Leoni ◽  
Michela Nocetti ◽  
Carlo Urbinati ◽  
Daniele Duca ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Infrared Spectroscopy ◽  
Near Infrared Spectroscopy ◽  
Near Infrared ◽  
Bending Strength ◽  
Prediction Models ◽  
Castanea Sativa ◽  
Modulus Of Rupture ◽  
Current Standard ◽  
Standard Samples

Near infrared spectroscopy (NIR) is a technique widely used for the prediction of different chemical-physical features of wood. In this study, the technique was used to assess its potential to predict the mechanical characteristics of wood. Castanea sativa samples of three different European provenances were collected and laboratory tests were performed to assess the mechanical properties of wood samples. Modulus of elasticity (MOE), load-deflection curve and modulus of rupture (MOR) were calculated by using INSTRON machine with three points bending strength with elastic modulus, while density (D) was calculated according to the current standard. Samples were then analysed by means of NIR spectroscopy. The raw spectra were pre-processed and regression models were developed. Variables selection techniques were used to improve the model performance. In detail, MOE regression model returned an error of 696.01 MPa (R2=0.78). Instead, MOR and D prediction models must be further investigated on a wider number of samples considering the high variability in physical characteristics of chestnut wood. The results demonstrated the possibility to use NIR technique for the prediction of the mechanical properties of wood providing useful indications in evaluation-screening processes. Indeed, the presence of the principal wood compounds (cellulose, hemicellulose and lignin) and their influence in the characterisation of mechanical stress reactions were confirmed.

scholarly journals Effects of modification with glutaraldehyde on the mechanical properties of wood

Holzforschung ◽  
2010 ◽  
Vol 64 (4) ◽  
Author(s):  
Zefang Xiao ◽  
Yanjun Xie ◽  
Holger Militz ◽  
Carsten Mai
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Scots Pine ◽  
Compression Strength ◽  
Bending Strength ◽  
Weight Percent Gain ◽  
Strength Loss ◽  
Modulus Of Rupture ◽  
Finite Span ◽  
Decreasing Ph

Abstract Scots pine (Pinus sylvestris L.) sapwood was treated with glutaraldehyde (GA) and magnesium chloride (MgCl2) as a catalyst. The effects of treating conditions on the mechanical properties were examined. The weight percent gain (WPG) of thin veneer strips after leaching was highest at pH 4.0–4.5 and tensile strength measured in zero-span strength and finite-span strength decreased with decreasing pH in a range of 3.5–5.5. Sole treatment with MgCl2 also gradually decreased the tensile strength up to 25% with decreasing pH. At a fixed GA concentration (1.2 M), increasing MgCl2 concentration linearly diminished tensile strength. Conversely, increasing GA at a fixed MgCl2 concentration (1.5%) displayed the same effect, whereas in both cases zero-span strength loss was higher than finite span-strength loss. GA treatment of Scots pine sapwood stakes did not affect the modulus of rupture and the modulus of elasticity, but significantly reduced work to maximum load in bending and impact bending strength indicating embrittlement of wood. At the same time, compression strength increased with increasing WPG of GA. It is assumed that embrittlement caused by hydrolysis and crosslinking of cell wall polymers is compensated by enhanced compression strength thereby resulting in unchanged bending strength.

scholarly journals Improvement of water resistance and mechanical properties of fast-growing poplar with bio-based isobornyl methacrylate monomer

BioResources ◽  
2020 ◽  
Vol 15 (2) ◽  
pp. 2356-2370
Author(s):  
Ji Xu ◽  
Zhaolan Zhai ◽  
Xingyan Yan ◽  
Zhanqian Song ◽  
Shibing Shang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Water Resistance ◽  
In Situ Polymerization ◽  
Forest Tree ◽  
Ethanol Solution ◽  
Modulus Of Rupture ◽  
X Ray Diffraction ◽  
Simple Method ◽  
Fast Growing ◽  
Methacrylate Monomer

Fast-growing poplar has become an extensively planted fast-growing forest tree species because of its short plantation rotation, lightweight character, and strong adaptability. However, fast-growing poplar usually exhibits some disadvantageous properties, such as inferior mechanical properties, high hygroscopicity, and poor dimensional stability, which limits its applications to a great extent. Herein, a simple method for improving the water resistance and mechanical properties of fast-growing poplar wood using the biobased monomer isobornyl methacrylate (IBOMA) was investigated. Wood/PIBOMA composites were prepared by impregnating the wood matrix with IBOMA ethanol solution, and then the IBOMA in the wood matrix was heated to initiate in situ polymerization. Field emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD) were used to investigate the properties of fast-growing wood/PIBOMA composites. The results showed that the IBOMA successfully penetrated the wood structure and polymerized in the cell walls and cell lumens. Thereby, the water resistance and mechanical properties of the fast-growing poplar were effectively improved. In addition, the water uptake of the wood decreased from 168.3% to 35.8% after impregnation with the 90% IBOMA solution. The modulus of rupture (MOR), modulus of elasticity (MOE), and compression strength (CS) of the 90% wood/PIBOMA composites were increased by 82.7, 28.6, and 2.3%, respectively.

scholarly journals Mechanical and Physical Properties of Particleboard from Untreated and Treated Kenaf Particles

2019 ◽  
Vol 16 (1) ◽  
pp. 60
Author(s):  
Nur Liyana Aifa Mahammad Asri ◽  
Ainil Idzaty Mohamed Anwar ◽  
Nur Atiqah Najib ◽  
Judith Gisip
Keyword(s):  
Mechanical Properties ◽  
Physical Properties ◽  
Bending Strength ◽  
Phenol Formaldehyde ◽  
Alkali Treatment ◽  
Thickness Swell ◽  
Strength Properties ◽  
Resin Content ◽  
Modulus Of Rupture ◽  
Minimum Requirements

Composite panels were manufactured from kenaf particles and treated with two different alkali treatments using 2% NaOH and 2% KOH with resin contents of 8% and 10% of phenol formaldehyde (PF) at medium density of 650kg/m3. The objectives of this study were to determine the mechanical properties in terms of its modulus of rupture (MOR), modulus of elasticity (MOE) and internal bond (IB), and physical properties namely thickness swelling (TS) and water absorption (WA) of treated kenaf board. The mechanical and physical tests were performed according to the Malaysian Standard (MS1787:2004). The minimum requirements value for MOE, MOR and IB were 2000 MPa, 14 MPa and 0.45 MPa respectively for furniture grade particleboards for use in humid conditions (PF2). According to Malaysian specifications for physical properties, the maximum requirement for thickness swell is 15%. Results indicated that both treated boards with NaOH and KOH showed an increase in strength properties compared to untreated particleboard. Particleboard treated with KOH exhibited the highest MOR and MOE values, while board with NaOH treatment gave the highest IB value. The boards with treated particles gave better performance in terms of physical properties. There were no significant differences in mechanical properties (MOR, MOE and IB) and physical properties for the different alkali treatment. The values of bending strength and IB strength increased with an increase in resin content, while TS and WA increased with a decrease in resin content. In conclusion, NaOH and KOH treated kenaf particles improved board performance and could be considered as an alternative material for particleboard production.

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.

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 ANALISIS KELAYAKAN SIFAT FISIK DAN MEKANIK KOMPOSIT GIPSUM BERPENGUAT SERAT ALAM SISAL SUMBAWA SEBAGAI PAPAN PLAFON

2019 ◽  
Vol 3 (3) ◽  
pp. 20-23
Author(s):  
Asywendi Rukini
Keyword(s):  
Mechanical Properties ◽  
Bending Strength ◽  
Physical And Mechanical Properties ◽  
Modulus Of Rupture ◽  
Sisal Fiber ◽  
Fiber Direction ◽  
Sisal Fibre ◽  
Fibre Amplifier ◽  
Physical Testing ◽  
Discontinuous Fiber

The gypsy composite ceiling of the sisal fibre amplifier is a potential environmentally friendly alternative replacing the commercial gyssum without fiber or a gypsy sum reinforcing fiber synthesis. In this study, manufactured a gypsy composite ceiling of a Sumbawa sisal fiber with a faction composition of the volume of 65% of a gypsy, cement 29% and sisal fiber 6%. The direction of fiber is variated with four conditions namely continuous fibre (SC) fiber woven (SW), discontinuous fibre (SDC) and hybrid fiber (SH). As a comparison of the use of Gypsy board without fiber with a fraction of the volume of a gypsy 65% and cement 35%. Then carried out physical testing (density test and water absorption) and mechanical testing of broken forces (modulus of rupture/MOR) and bending strength (modulus of elasticity/MOE). The results of physical testing showed an increase in the the density of a gypsy board of the 1.17 g/cm3 to ± 1.71 g/cm3 after reinforced fiber and absorbent water ± 42.76% for all fiber board. For the mechanical properties of MOR and MOE the highest value is produced by specimen with a directional continuous fiber direction (SC) of 10.58 MPa and 3890.6 MPa. And the lowest is owned specimen with a random discontinuous fiber direction (SDC) of 5.05 MPa and 1530.2 MPa. However, the value of fracture and bending of the SDC specimen is still higher than the commercial gypsy board without fiber. Feasibility analysis is performed by comparing the physical and mechanical properties of JIS A 5417-1992 and ISO 8336-2017 standards.

Mechanical Properties of Particleboard from Oil Palm Trunk (Elaeis Guineensis Jacq) Using Phenol Formaldehyde Adhesive in Relation to Particle Sizes and Board Thickness

2013 ◽  
Vol 372 ◽  
pp. 101-103
Author(s):  
Mohd Arif Fikri Mohd Adnan ◽  
Jamaludin Kasim ◽  
Siti Noorbaini Sarmin
Keyword(s):  
Mechanical Properties ◽  
Particle Size ◽  
Forest Fires ◽  
Oil Palm ◽  
Bending Strength ◽  
Elaeis Guineensis ◽  
Phenol Formaldehyde ◽  
Modulus Of Rupture ◽  
Oil Palm Trunk ◽  
Board Thickness

High demand for wooden materials and rises in agricultural areas and forest fires increased the importance of composite particleboard instead of using solid woods. Particleboards are among the most popular materials used in interior and exterior applications. The objective of this study was to examine the physical and mechanical properties of phenol formaldehyde particleboard made from oil palm trunk (OPT) with 11% resin content. Two different board thicknesses were use; 12mm and 16mm. The particle size use in this study was 2mm and 1mm. Phenol formaldehyde (PF) was used as the binder. The result showed that modulus of rupture and modulus of elasticity were perform better at 16mm board thickness with 1.0mm particle size and meet the standard. The internal bonding strength was parallel with bending strength.

scholarly journals Influence of aggressive media on mechanical properties of wood-polymer composites

2020 ◽  
pp. 16-20
Author(s):  
T. V. Zhdanova ◽  
E. M. Chaika ◽  
T. A. Matseevic ◽  
E. S. Afanasiev ◽  
A. A. Askadskii
Keyword(s):  
Mechanical Properties ◽  
Flame Retardants ◽  
Bending Strength ◽  
Wood Flour ◽  
Wood Polymer ◽  
Two Samples ◽  
Long Time ◽  
Wood Polymer Composites ◽  
Wood Content ◽  
Specific Impact

Mechanical properties of two samples of decking boards were measured after exposure in rain and chlorinated water, in ice, and in a mixture of gasoline and water in different concentrations from 1 to 7%. Samples consisting of 60% wood flour, 30% polyvinyl chloride and 10% additives were used for measurements. Additives are flame retardants, stabilizers, modifiers and dyes. The mineral filler CaCO3 was used as modifiers. For sample №1, the CaCO3 content was 42% and the wood content was 18%. For sample №2, the CaCO3 content was 24% and the wood content was 36%. As a result of measurements after exposure for 150 days, it was found that the specific impact strength increases by 120%, the bending strength decreases by 60%, and the Shore D hardness decreases by a maximum of 10%. Consequently, decking boards can be confidently used for a long time, since a number of properties almost do not change, but even increase, and some decrease in strength remains within acceptable values.

scholarly journals Development and characterization of hybrid coconut/glass fibers reinforced low density polyethylene composites for bumper application

10.30544/453 ◽  
2020 ◽  
Author(s):  
Akinlabi O. David ◽  
Ibeh Stanley Chukwuemeka ◽  
Enegide E. Osther ◽  
Garba N. Salihu
Keyword(s):  
Mechanical Properties ◽  
Glass Fiber ◽  
Bending Strength ◽  
Glass Fibers ◽  
Chemical Properties ◽  
Modulus Of Rupture ◽  
Low Density Polyethylene ◽  
Low Density ◽  
Coconut Fiber ◽  
Polyethylene Matrix

The EU's End of Life Vehicles (ELV) regulations are forcing car manufacturers to consider the environmental impact of their production and possibly shift from the use of synthetic materials to the use of agro-based materials. However, poor mechanical properties and certain manufacturing limitations currently limit the use of agro-based materials to non-structural and semi-structural automotive components. This research is focused on a composite of hybrid coconut/glass fiber as reinforcement in recycled low density polyethylene matrix alone to enhance the desired mechanical properties for car bumper as automotive structural components. X-ray fluorescence analysis conducted on coconut fiber showed the presence of silica and alumina materials make coconut fibre a choice one. Morphology analysis was performed using scanning electron microscopy (SEM), which reveals that there are small discontinuities and reasonably uniform distribution of the reinforcement fibers and the reinforced low density polyethylene (RLDPE) binder resulting to better mechanical properties. Physic-chemical properties that directly affect developed composite such as variation of Density, Water Absorption, Tensile Strength, Bending strength, Modulus of rupture, Impact Strength and Hardness Values were investigated for both unhybridized and hybridized developed composite. The study shows the successful development of composites of coconut fiber (CF) hybridized with glass fiber (GF) and reinforced low density polyethylene (RLDPE) binder using a simple molding technique. Hybridized samples (CF-GF/RLDPE) showed higher strength when compared to un-hybridized (CF/RLDPE) composites. Better microstructural bonding exists with 25% and 30% wt CF-GF composite resulting in good mechanical properties for the hybridized composites. The grades of composites obtained in the course of this study are applicable in the production of low strength car bumpers.

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