Physics and Mechanical Wood
Ebrahim Khosravi; Amir Lashgari; Mehran Roohnia; Ahmad Jahan latibari; Ajang Tajdini
Abstract
Background and objectives: From the limitations of detecting the amount of useful life remaining in the components of the structures in the conditions of use with acoustic methods is the impossibility of calculating the modulus of elasticity due to the impossibility of removing the part from the structure. ...
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Background and objectives: From the limitations of detecting the amount of useful life remaining in the components of the structures in the conditions of use with acoustic methods is the impossibility of calculating the modulus of elasticity due to the impossibility of removing the part from the structure. Therefore, most of the classifications during use in the components of structures such as historical buildings are based on measuring the speed of sound. In this research, to calculate the local and global density with the method of pin penetration rate in wooden tie in order to calculate the amount of their remaining useful life by combining stress wave and free longitudinal vibration methods has been studied. There was no significant difference between the values of global sound velocity and global modulus of elasticity with the local results of these factors at the five tested points in each of the wooden tie.Methodology: The number of three saturated wooden tie from Iran Railway Company and with the dimensions of 15x25x260 cm, which are made of beech species (Fagus orientalis) and the density was measured by pin penetration method at 5 points of each wooden tie (50 cm distance between each point) and the average results of 5 points were compared with the results of ISO 13910 standard method. The stress wave test was carried out at the same 5 points of density determination by pin penetration rate method to determine the local modulus of elasticity and the results of each point were compared with the global modulus of elasticity of the beam. Longitudinal vibration test was also performed to calculate the damping factor values of the samples.Results: The results showed that there was no significant difference at the 95% level between the values calculated with both the ISO 13910 standard methods and the pin penetration rate method, and there was a favorable linear correlation between the results of the two methods. According to the results, there was no significant difference between the global sound speed of the beams and their local sound speed in any of the five measured points at the 95% level and there was a linear correlation between the values of the global sound speed and each of the five local points. There was no significant difference at the 95% level between the values of the global modulus of elasticity and the values of the local modulus of elasticity calculated in each of the five points. Also, there was a linear correlation between the values of the global modulus of elasticity and the results of the local modulus of elasticity in each of the five points. There was an exponential correlation between the values obtained from the global modulus of elasticity and the damping factor of each of the wooden tie.Conclusion: The equality of density according to the ISO 13910 standard method and the nail penetration method, as well as the equality of the modulus of elasticity calculated by the stress wave method and the free longitudinal vibration method, make it possible to obtain all the data required for calculations without removing the part from the structure. The remaining strength of wooden components should be provided according to EN338 standard.
Ali Hasanpoor tichi; Hadi Gholamiyan
Abstract
In this study , Effect of nano cellulose Fiber gel bacteria as reinforcer on physical, mechanical and morphological properties of composites made of bagasse and cement has been studied. Nano variable factors in three levels (0, 1 and 3 % by weight of cement), the mixing ratio of bagasse as lignocellulosic ...
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In this study , Effect of nano cellulose Fiber gel bacteria as reinforcer on physical, mechanical and morphological properties of composites made of bagasse and cement has been studied. Nano variable factors in three levels (0, 1 and 3 % by weight of cement), the mixing ratio of bagasse as lignocellulosic material with Portland cement, in three levels (90:10, 80:20, 70:30%) was equal to the dry weight of cement. The target density 1.1 g/cm3 and 5% calcium chloride for all treatments were considered as Fixed factors. The mechanical and physical properties of composites includes modulus of rupture, modulus of elasticity, internal bonding, thickness swelling after 2 h and 24 h immersion in water and density of boards were measured according to the standard DIN-EN-634. In this study, to investigate the morphological properties of composites and how to distribute Nano, microscopic images (SEM) were taken from the broken cross-section of the samples. The results showed that boards made with nano fiber cellulose had more modulus of rupture, modulus of elasticity and internal bonding. The results also showed that with increasing nano, density, dimensional stability of the boards and heat hydration of cement mortar increased. The results from microscopic imaging (SEM) showed that cellulose nanofiber can fill the pores of the composite and create a uniform structure, thus improved the strength of the boards.
Composite wood products
ali hasanpoor tichi; Fardad Golbabaei; hadi Ghasemi; mojtaba rezanezhad
Abstract
In this study, the effect of nano gel wollastonite on physical, mechanical and morphological properties of composites made of bagasse and cement has been investigated. The mixing ratio of bagasse as lignocellulosic material with Portland cement at three levels (15:85, 25: 75 and 35: 65%) and nano-wollastonite ...
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In this study, the effect of nano gel wollastonite on physical, mechanical and morphological properties of composites made of bagasse and cement has been investigated. The mixing ratio of bagasse as lignocellulosic material with Portland cement at three levels (15:85, 25: 75 and 35: 65%) and nano-wollastonite at three levels of 0, 3 and 7% were considered as the variables of this study. The cake density of all boards were 1.1 g / cm3 and calcium chloride booster 5% for all treatments were considered as constant factors. Mechanical and physical properties of the specimens include modulus of rupture, modulus of elasticity, internal bonding, thickness swelling after 2 and 24 soaking hours in water and density of boards according to DIN-EN-634 and fire resistance (weight loss percentage) according to standard ISO-11925 were measured. In this study, the hydration temperature of a mixture of cement, bagasse and nano-wollastonite was measured using a thermocouple and flux. Also, microscopic images (SEM) of samples were prepared to investigate the morphological properties of composites and their distribution. The results showed that by increasing the amount of nano-wollastonite, the percentage of weight loss boards decreased, the heat of hydration and the physical and mechanical properties improved. The modulus of rupture, modulus of elasticity, and internal bonding of boards decreased with increasing bagasse content and the maximum value was obtained using 15% bagasse. The results also showed that with increasing bagasse content in boards, there was a significant increase in thickness swelling of boards. Inference from microscopic imaging (SEM) showed that the optimum level of nano-wollastonite can fill the empty holes and create a uniform structure and thus improve the properties of the boards.
Physics and Mechanical Wood
Parastoo Majdabadifarahani; Mehran Roohnia; amir lashgari
Abstract
DOR:98.1000/1735-0913.1398.34.87.66.1.1585.1588 This study deals with the possibility of evaluation and estimating the wood density in Quercus castaneifolia and Fagus orientalis. Wood samples were prepared and cut firstly in 4×20×30 cm (thickness×width×length). Then their density ...
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DOR:98.1000/1735-0913.1398.34.87.66.1.1585.1588 This study deals with the possibility of evaluation and estimating the wood density in Quercus castaneifolia and Fagus orientalis. Wood samples were prepared and cut firstly in 4×20×30 cm (thickness×width×length). Then their density was calculated after 72 hours of conditioning in an oven at 60°C temperature. In thermography process, the temporal temperature was monitored in 1st, 5th, 10, 20, 30, 45 and 60th minutes of cooling (monitoring steps). Investigating the effects of shape factor and dimension on thermographic density evaluation errors, the specimens were cut down in two more steps to 3×20×30 cm and 2×15×20 cm and the course of thermography experiments was repeated. The relationships of shape factor, density and the ratio of density to the shape factor with the logarithmic cooling rate were evaluated separately. Results showed that density without considering the shape factor variations was not sufficiently correlated to the cooling rate. But the ratios of the density to their proper shape factors were promising for the density evaluations from the cooling rates. However, it is suggested to revise this non-destructive method using a larger variety of the wood specimens and species.
Composite wood products
Ali Hasanpoor tichi; Behzad Baziyar
Abstract
In this study the effect of nano gel wollastonite usage in three level (0 , 5 and 10 percent per dry by weight of the cement) and the mixture ratios of lingocellulosic material to cement in three level 10:90, 20:80 and 30:70 on physical, mechanical , microscopic and biological properties of composite ...
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In this study the effect of nano gel wollastonite usage in three level (0 , 5 and 10 percent per dry by weight of the cement) and the mixture ratios of lingocellulosic material to cement in three level 10:90, 20:80 and 30:70 on physical, mechanical , microscopic and biological properties of composite made from rice straw fibers- cement was investigated. Three replicates for each treatment and 27 experimental boards were manufactured. Specimens were prepared according to DIN- EN634 standard test methods to measure mechanical and physical properties. Mechanical and physical properties including static bending strength, modulus of elasticity, interior bonding(IB),water absorption after 2 and 24 hours immersion in the water , density and decay resistant (loss weight) were measured. Micro- structural properties of composites were evaluated by SEM images. The results showed that, bending strength , modulus of elasticity , interior bonding and density were significantly increased with increasing Nano gel wollastonite . Also, with increasing Nano gel wollastonite , dimensional stability and decay resistance were increased in comparison with the control sample. Results of scanning electron microscopy showed that the calcium hydroxide formed hydrated calcium silicate gel (C-S-H gel) after addition the Nano gel wollastonite . SEM images showed that the micro- structure of the boards were improved by increasing the nano- wollastonite content.
Pulp and paper
Mehrnoosh Tavakoli; saraeyan ahmad reza; hossein resalati; ali ghasemian
Abstract
The present study was carried out aiming to investigate the effect of using Deinked Mixed Office Waste Pulp (MOW) on the properties of Alkaline Peroxide Mechanical Pulp (APMP) from cotton stalk. APMP pulps was prepared using chelating agents such as Na2SiO3 and DTPA (control sample) and without ...
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The present study was carried out aiming to investigate the effect of using Deinked Mixed Office Waste Pulp (MOW) on the properties of Alkaline Peroxide Mechanical Pulp (APMP) from cotton stalk. APMP pulps was prepared using chelating agents such as Na2SiO3 and DTPA (control sample) and without these agents in two-stage pulping withL/Wratio 6:1(ml/g), 20 minutes impregnation time at 70 0Cfor firststage, 60 minutes impregnation at 75 0Cfor second stage. Also, pulp was preparedfrommixed office waste paper, whichweredeinked with conventional flotation and then each pulp was separately refined up to about 300 ml CSF. The handsheets were made from control sample pulps, APMP without chelating agents, MOW deinked pulp and mixing with 10%, 20% deinked pulp with control APMP. Physical and mechanical properties were determined using TAPPI standard methods. Deinked MOW pulp had the maximum values of density, brightness, strength properties and APMP pulp without chelating agents had the minimum values. Among mixed pulps, APMP pulp containing 20% deinked MOW pulp showed the maximum value of density, brightness, burst index and tear index.
Hanieh Ghasemi; Ahmad Jahan Latibari; Abolfazl Karegarfard; Amir Lashgari
Abstract
The impact of the addition of different amounts of canola straw to the composition of the hardwood particles for the production of particleboard was investigated. Four levels (0, 15, 30 and 45%) of Canola particles were added to hardwood particles and then particles were blended with 12% urea resin (based ...
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The impact of the addition of different amounts of canola straw to the composition of the hardwood particles for the production of particleboard was investigated. Four levels (0, 15, 30 and 45%) of Canola particles were added to hardwood particles and then particles were blended with 12% urea resin (based on the oven dry weight of the particles). Boards at three densities of 550, 600 and 650 kg/m3 were produced. The flexural and internal bonding strength and water absorption and thickness swelling after 2 and 24 hours immersion in water of the boards were determined using appropriate EN standard test methods. Addition of different amounts of canola particle to the hardwood particles did not change either modulus of rupture or modulus of elasticity of the boards, but the internal bonding of the boards was reduced. As the dosage of the canola particles increased, both water absorption and thickness swelling were reduced. Increasing the density of the boards increased both strength and dimensional stability.
ّFahimeh Shabanalizadeh; Mohammad reza Dehghani firoz abadi; Abolfazl Karegarfard; Mehrab Madhoshi
Abstract
Utilization of kenaf core and stalk for the production of medium density fiberboard was investigated. Control boards were produced using poplar wood fibers and compared with kenaf boards. Urea formaldehyde resin was used. Medium density fiberboards were made at two densities of 0.55 and 0.75 g/cm3. ...
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Utilization of kenaf core and stalk for the production of medium density fiberboard was investigated. Control boards were produced using poplar wood fibers and compared with kenaf boards. Urea formaldehyde resin was used. Medium density fiberboards were made at two densities of 0.55 and 0.75 g/cm3. Six combinations of variable were tested and for each combination of variables, 3 replications and the total of 18 laboratory MDF boards were produced. The kenaf core and stalk fiber dimensions and the mechanical and physical properties of the MDF boards were measured. Factorial experimental design was used for statistical analysis of generated data. Results showed that average length of kenaf core and stalk fiber are 3.607 and 0.78 mm, and their respective diameters are 41.48 and 36.76 μm. The results of modulus of rupture, modulus of elasticity, internal bonding and thickness swelling after 2 and 24 hours immersion in water showed that kenaf core fiberboard with the density of 0.75 g/cm3 are above the required values for these boards which indicate that these properties are comparable with MDF from wood. It can be expressed that kenaf core fibers can substitute the poplar wood fiber for MDF production. The modulus of rupture, modulus of elasticity and internal bonding of MDF boards produced using kenaf core was improved as the density of the boards increased. The thickness swelling after 2 and 24 hours immersion in water was comparable to poplar fiberboard. Kenaf stalk fiberboard showed lower mechanical and physical properties due to the presence of bark fibers.
Mohammad hadi Aryaei monfared; Hossein Tavakoli; Hossein Hosseinkhani
Abstract
One of the lesser known local woody species of the Zirkooh-Qhaen in the east of Iran is Ammodendron persicum with the traditional name of Divdal. In this study three selected logs were used for study of wood properties. For the first time wood of this desert species was studied from different physical ...
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One of the lesser known local woody species of the Zirkooh-Qhaen in the east of Iran is Ammodendron persicum with the traditional name of Divdal. In this study three selected logs were used for study of wood properties. For the first time wood of this desert species was studied from different physical and anatomical aspects. The results showed that Ammodendron ʼs wood is a ring -porous hardwood that all parts of its cross section have long rays that is visible with naked eye. In the study of physical properties of Ammodendron̛ ҆s wood apparent density and dry one respectively was 1.125 and 0.92 g/Cm3 that put this wood to the very dense category.
Physics and anatomy
Neda Sakhavati; Moslem Akbari nia; Hoshangh Zanganeh
Abstract
Cerasus mahaleb (L.) Mill is among the important broad-leaved trees in Zagros forests. Good bending property and the pleasant aroma helped the tree species to find a long history of rural and local uses. Wood consumption is closely influenced by the physical, biometric and other engineering properties. ...
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Cerasus mahaleb (L.) Mill is among the important broad-leaved trees in Zagros forests. Good bending property and the pleasant aroma helped the tree species to find a long history of rural and local uses. Wood consumption is closely influenced by the physical, biometric and other engineering properties. Three sound trees were harvested and tested according to ASTM-D143 standards testing procedures. Results showed that Cerasus mahaleb (L.) Mill has semi-heavy wood with high bending ability. Its compression strength parallel strain was measured as 48.45 MPa. The average fiber length and fiber diameter was 0.71 mm and 19.85 m respectively. Mean volume shrinkage and swelling was measured as 6.09% and 6.69% respectively. The radiant and tangent shrinkage and swelling after 2 and 24 hour immersion in water was 19.65%, 19.74%, 19.9%, 19.89%, 20.62% and 21.16% respectively. Mean annual diameter growth as well as mean height growth were 4.96 mm and 0.31 m respectively.
Kamyar Salehi; Fardad Golbabaei; Saeed Mahdavi; Abas Fakhryan
Abstract
The characteristics of five common varieties of sugarcane cultivated in the southern Iran, including cp57-614, sp70-1143, cp69-106, cp48-103, and nco310 were evaluated. The characteristics measured were fiber dimension, papermaking coefficients, fiber yield, density and chemical component. cp69-106 revealed ...
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The characteristics of five common varieties of sugarcane cultivated in the southern Iran, including cp57-614, sp70-1143, cp69-106, cp48-103, and nco310 were evaluated. The characteristics measured were fiber dimension, papermaking coefficients, fiber yield, density and chemical component. cp69-106 revealed the longest fiber with the average length of 1.55 mm whereas cp57-614 had the shortest fiber with average length of 1.39 mm. The cp48-103 and cp69-106 were ranked as having the widest and narrowest fiber diameter as 25.38 and 20.42 micron respectively. The measurement of the density at 12% moisture content showed that sp70-1143 with 0.35g/cm-3 provide the highest value and the cp57-614 possessed the lowest density measured at 0.17g.cm-3. There existed statistically significant differences among other fiber characteristics and papermaking coefficients. In general, the result indicated that cp69-106 provides the optimal characteristics in comparison with the other varieties based on papermaking specifications.
Composite wood products
Mohammad Arabi; Mohammad mehdi Faezipoor; Mohammad Layeghi; Ali akbar Enayati
Abstract
The purpose of this study was to investigate which equation (Linear, Exponential equation and quadratic) can describe exactly the interaction effect of particle size and adhesive percent and predict mechanical properties of particleboard (modulus of rupture, modulus of elasticity and bending strength). ...
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The purpose of this study was to investigate which equation (Linear, Exponential equation and quadratic) can describe exactly the interaction effect of particle size and adhesive percent and predict mechanical properties of particleboard (modulus of rupture, modulus of elasticity and bending strength). For this work three levels of density including 0.65, 0.7, and 0.75 g/cm3 and also, three levels of adhesive content including 8, 9.5, and 11% and four levels of slenderness ratio of particles including 46.35, 33.7, 21.51 and 12.87 were used. After conducting the experiment and preparing the data, three kind of equation (linear, quadratic and Exponential equation) for each mechanical property based on slenderness of particles, density and adhesive percent obtained. The result indicated there was no correlation between mechanical properties of particleboard and quadratic equation but there were good correlations between linear and Exponential equation. Also the result indicated that Exponential equation can describe efficiently the simultaneous effect of slenderness and adhesive present on the mechanical properties of particleboard, and it can predict better mechanical properties than linear equation.
Pulp and paper
saeed mahdavi; masoudreza habibi; Abbas Fakhryan roghani; Kamyar Salehi
Abstract
Oil seed rape (Brassica napus) planting is increasing as the Iranian Ministry of Agriculture Jehad policy to provide supply of oil food in Iran. The objective of this study is utilization of rapeseed straw as a considerable raw material for paper industry whereas there is shortage of lignocellulosic ...
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Oil seed rape (Brassica napus) planting is increasing as the Iranian Ministry of Agriculture Jehad policy to provide supply of oil food in Iran. The objective of this study is utilization of rapeseed straw as a considerable raw material for paper industry whereas there is shortage of lignocellulosic material in Iran. Sampling was carried out from two varieties of oil seed rape, Hiola 401 and PF, based on initial compatibility experiments and yield in Mazandaran province from Baye-colla research station. The results show that at least 4 ton/hect. oven dry rapeseed straws are available. There were significant differences between fiber width, lumen diameter, ash and extractive contents in two varieties. Rapeseed straw as a lignocellulosic material was achieved at 10 score according to the five characteristics consisting of phytology, fiber dimension, fiber yield, chemical components and appearance feature. This means more studies are necessary to make a final assessment.
Physics and anatomy
Shamohammad Amiri; Ahmad Jahan latibari
Abstract
For the determined of Anatomical, Chemical and Physical characteristics of SAXAUL wood (Haloxylon persicum) from Haresabad-e-Sabzevar research station located in Khorasan-e- Razavi province 4 trees from this specie were selected and cut. Samples transferred to the Chemical laboratory in Alborz-e-Karaj ...
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For the determined of Anatomical, Chemical and Physical characteristics of SAXAUL wood (Haloxylon persicum) from Haresabad-e-Sabzevar research station located in Khorasan-e- Razavi province 4 trees from this specie were selected and cut. Samples transferred to the Chemical laboratory in Alborz-e-Karaj research center for studies. Anova-1 in mstat-c statistical software was used for statistical analysis. Anatomical characteristics measured Fiber length, Fiber diameter, lemun and cell wall thickness 336.22, 13.61, 3.68 and 4.99 micron, respectively. Paper making coefficients were also measured. Mix up coefficient; Flexibility coefficient and Rankle coefficient were 24.72, %27.05 and %2.71, respectively. Chemical characteristics measured cellulose, lignin, alcol-acetone soluble extractives, NaoH 1% soluble extractives, hot water soluble extractives and ash 46.50%, 29.54%, 7.37%, 16.25%, 6.92% and 1.27%, respectively. Physical characteristics measured of density, dry density and critical density 1024.25, 1003.83 and 913 gr. per cubic centimeter.
Composite wood products
Amir Nourbakhsh; Abolfazl Kargarfard
Abstract
In this research utilization of Poplar Insulation particleboard at two different level of density (0.35, 40, 45 and 50gr/cm3) and press time (2, 3 and 4 min) were considered. Based on the DIN standard physical and mechanical properties including MOR, MOE, IB and thickness swelling (after 2 and 24 immersion ...
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In this research utilization of Poplar Insulation particleboard at two different level of density (0.35, 40, 45 and 50gr/cm3) and press time (2, 3 and 4 min) were considered. Based on the DIN standard physical and mechanical properties including MOR, MOE, IB and thickness swelling (after 2 and 24 immersion in water) were tested. Based on the factorial experimental design at completely random test was analysis. The effect of density from 0.35 to 0.50gr/cm3, MOR, MOE and IB were increased and thickness swelling after two and 24 hours immersion in water were decreased .Moreover the effect of Press time from 2 to 4 min. MOR and MOE increased and at 3 min. IB was increased.
Physics and anatomy
Saeed Mahdavi; Abdolrahman Hosseinzadeh; Hossein Familian; masoudreza habibi
Abstract
Cross sectional disks were cut at breast height from three 17-year-old trees of E.camaldulensis grown in Pasand research station in Mazandaran province. Ring width, wood density, and fiber dimension were measured for each two rings from pith to the bark. Overall average disks, fiber length, fiber width, ...
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Cross sectional disks were cut at breast height from three 17-year-old trees of E.camaldulensis grown in Pasand research station in Mazandaran province. Ring width, wood density, and fiber dimension were measured for each two rings from pith to the bark. Overall average disks, fiber length, fiber width, lumen diameter, and cell wall thickness were measured at 758, 15.93, 8.63, and 3.65 micrometer respectively. Mean values for the oven dry and basic. Density was 0.708 g/cm3 and 0.552 g/cm3. Cross sectional \ growth rate and wood production for the trees were measured at 11.1 mm and 12.3 m3/ha./year respectively. Chemical compositions of the wood consist or cellulose, lignin, extractives (in acetone soluble) and ash were measured at 47.44%, 30.87%, 6.96%, and 0.27% respectively. The result showed that E.camaldulensis is classified as short fiber hardwood with low frequency. Fiber dimensions and density slightly increased from pith to the bark. There was high significant correlation between cell wall thickness and density, while; there was no significant correlation between ring width and the others. Among the properties studied, cell wall thickness and fiber length showed the most variations.
