Mechanical conversion of wood and wooden fittings
Hadi Gholamiyan
Abstract
In this study, the effect of corona treatment on improving the durability of nitrocellulose and polyurethane coatings used in the wood furniture industry before and after weathering investigated. The boards made from poplar and beech were coated by an automatic film applicator after corona treatment ...
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In this study, the effect of corona treatment on improving the durability of nitrocellulose and polyurethane coatings used in the wood furniture industry before and after weathering investigated. The boards made from poplar and beech were coated by an automatic film applicator after corona treatment and accelerated for 30 days in a weathering machine. Then, the contact angle, abrasion resistance, and pull-off adhesion testing to the wood surface coatings were analyzed. The results showed that corona treatment reduced contact angle in wooden species and the highest contact angle reduction found in beech wood. Also, the results of the adhesion test showed that the highest adhesion was related to the polyurethane coating and after weathering, the adhesion of the coatings decreased, but the use of corona treatment, in addition to increasing the adhesion strength before weathering, could significantly improve adhesion after weathering. The results of the abrasion test showed that the wear resistance increased in wooden species due to the coating, and the highest amount observed in the beech-coated with polyurethane. After weathering, wear resistance was reduced in all samples, but using corona treatment increased resistance to abrasion. In general, it can say that the use of corona treatment can significantly (95%) improve the resistance to mechanical properties and durability of coatings before and after weathering and thus increase the durability of the furniture and wooden structures.
Mechanical conversion of wood and wooden fittings
Barat ali Keshtegar; Mehrab Madhoushi; Alimorad Rashidi; mahdi mashkour
Abstract
In this research, the effect of Polyvinyl acetate (PVAc) adhesive reinforced with modified carbon nanofibers (CNF) were studied in three levels (0%, 0.4%, 1.5%) on the strength properties of joints commonly in the furniture industry. Modified carbon nanofibers were used as chemically modified surface ...
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In this research, the effect of Polyvinyl acetate (PVAc) adhesive reinforced with modified carbon nanofibers (CNF) were studied in three levels (0%, 0.4%, 1.5%) on the strength properties of joints commonly in the furniture industry. Modified carbon nanofibers were used as chemically modified surface to improve the dispersion in polymer matrix. The bonding of the test specimens were made using of cut out medium density fiber board (MDF) pieces with desired dimensions and dowel wooden with 6, 8 and 10 mm in diameter, and penetration depth at three levels using polyvinyl acetate adhesive reinforced with modified carbon modified nanofiber. Totally, we have 27 treatments with three replicates. The evaluation of the bending moment capacity of test specimens made with freshly formulated adhesive carried out and the effect of other variables was performed on the joints made under tensile loading at a speed of 3 mm/min. The results showed that increasing the weight percent of carbon nanofibers, the diameter of the wooden dowel and the penetration depth and the moment capacity compared to the control samples was increased by 1.6, 1.5 and 1.3 times, respectively. The 0.4% w/w carbon nanofibers, 10 mm diameter and L3 wooden dowel penetration depth had the greatest effect on the strength of the joints.
Mechanical conversion of wood and wooden fittings
Morteza Nazerian; Alireza Rezaian; Mohamma Shamsiyan
Abstract
Bending strength of I-joist lightened via two methods of crinkleing and honeycombing using poplar species (Popolus deltoids) and eucalyptus (Eucalyptus spp) was studied. Investigated variables consisted of: a) type of flange, b) configuration of lightened core layer in web and c) thermal-pressure treatment ...
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Bending strength of I-joist lightened via two methods of crinkleing and honeycombing using poplar species (Popolus deltoids) and eucalyptus (Eucalyptus spp) was studied. Investigated variables consisted of: a) type of flange, b) configuration of lightened core layer in web and c) thermal-pressure treatment surface layers of web. Flange type at two levels: 1) LVL from poplar wood and 2) eucalyptus massive wood, configuration of web core layer at two level too: 1) crinkle and 2) honeycomb and type of treatment applied on surface layers of web which were prepared from poplar layies with 3 mm thick at two levels: 1) thrmo-compressed treated and 2) untreated veneers were selected. Mechanical properties of beam consisted of modulus of rapture (MOR) and modulus of elasticity (MOE) were selected and tested as dependent variables. Obtained results were analyzed in full factorial plot, statistically. After determination of results significance results, means of values were classified by Duncan Multiple Range Test (DMRT). Results showed that using LVL from poplar unlike its low density had higher MOR and MOE values compared with eucalyptuse massive wood. Besides, in order to lighten beam, using honeycomb configuration in web core layer gave more strength to beam in comparison with crinkle configuration. Treatment of surface layers of web had not effect on bending strength, statistically.
Mechanical conversion of wood and wooden fittings
Fardad Golbabaei; Reza Hajihassani; Kamyar Salehi
Abstract
With full respect for the principles of linking wood and conservation project Eldar pine because having good mechanical properties and availability of a wood structure in the form of pavilions chose alcove to the octagon without internal column with computer software Sketch up of Alborz research center ...
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With full respect for the principles of linking wood and conservation project Eldar pine because having good mechanical properties and availability of a wood structure in the form of pavilions chose alcove to the octagon without internal column with computer software Sketch up of Alborz research center with trees and landscaping of the complex was built. In making these structures all stages of the preparation of the wooden parts of drying are quite principled and dried in the open air during the six months were roof wood structure with the use of Eldar pine just Lambe was made in setting up the ceiling of solar connection on an octagonal timber wood using mortise and tenon mode and auxiliary metal was used. Sliding windows can be made to occupy less space. After completion of the period of three months to review the different pieces in different parts of the structure and measurements of physical densities, shrinkage and swelling and mechanical testing of hardness and impact resistance and protection review different parts of the fungal infection and decay structures was investigated. Since shortly after the beginning of the measure is going to change in the early stages of measuring statistically Darnbvdh but in the last stage of a decrease in density of about 5% and reduce the hardness of about 8% were signs of shrinkage and swelling in various parts of it to be seen.
Mechanical conversion of wood and wooden fittings
PANTEA OMRANI; Reza Eisapor
Abstract
The insertion of dowels into solid wood for furniture has been used for centuries. Recently, this simple technology has been upgraded. The objective of the research was to evaluate and compare the tensile strength of the joints made of wood dowel through new method “wood welding” and classical ...
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The insertion of dowels into solid wood for furniture has been used for centuries. Recently, this simple technology has been upgraded. The objective of the research was to evaluate and compare the tensile strength of the joints made of wood dowel through new method “wood welding” and classical method “using of glue”. Variables included dowel joints method (welding joint and joint with glue), dowel diameter (10 and 12 mm) and dowel surface (smooth and grooved). Members joint and dowel wood were hornbeam species (Carpinus betulus) and the used glue was polyvinyl acetate (PVA). The results showed that the types of joints, diameter and surface dowel, have significant effect on the tensile strength, so that welded joints, dowel diameter 12 mm and dowel grooved surface has the most tensile strength to other samples. The results also showed that in all cases, the strengths of the joints made by welding was more than the joints made by PVA glue.
Mechanical conversion of wood and wooden fittings
Mosayeb Dalvand; Ghanbar Ebrahimi; Kambiz Pourtahmasi
Abstract
In this study effect of staple length (penetration length) and its number in connection, on withdrawal capacity in face and edge of laminated veneer lumber (LVL) out of poplar was investigated. In this investigation, the staple with 3 and 4 cm penetration length and staple with 3, 4 and 5 cm penetration ...
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In this study effect of staple length (penetration length) and its number in connection, on withdrawal capacity in face and edge of laminated veneer lumber (LVL) out of poplar was investigated. In this investigation, the staple with 3 and 4 cm penetration length and staple with 3, 4 and 5 cm penetration length for withdrawal capacity in face and edge were used respectively. Number of staples at 4 levels (2, 3, 4 and 5) were chosen as a variable. Results have shown that withdrawal capacity in face significantly increases with increase of penetration length. Withdrawal capacity in edge increases drastically with increase of penetration length from 3 to 4 cm, but increase in penetration length from 4 to 5 cm had no significant effect. Withdrawal strength capacity in face has increased with increase of staples number. But, increase of staple number had no significant effect on withdrawal strength capacity in edge. Maximum withdrawal capacity was observed in joints fabricated with penetration length of staple 4 cm and number of 5 staples in face and minimum those were observed with penetration length 3 cm and number of 2 staples in edge.
Mechanical conversion of wood and wooden fittings
Ehsan Ketabi; Amir Lashgari
Abstract
In this study was to evaluate the impact of the truss structure on stiffness and stress distribution in the truss structural members. Made and synchronizes this structures with any Populus_ Nigra lumbers, in finally made 44 truss structure with 11 varying samples and 4 replicates. were used by two joint ...
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In this study was to evaluate the impact of the truss structure on stiffness and stress distribution in the truss structural members. Made and synchronizes this structures with any Populus_ Nigra lumbers, in finally made 44 truss structure with 11 varying samples and 4 replicates. were used by two joint like friction joints was created with Glue stick and dual joint was created with nails to the 4.5 cm and calculate the resistance trusses structures by mechanical testing machine with 12.5 mm/min loading speed and 3.5 KN than mechanical test results showed, Hip Girder truss most resistance stress distribution and were the least impact on the strength and distribution of tension truss structure is significant in 95%. To show the stress distribution on the members, modeling software was AutoCAD, Catia and finite element analysis software was ANSYS. In finally the results show that maximum stress concentration, failure to engage in experimental mode.
Mechanical conversion of wood and wooden fittings
Soheila Zamaninasab; amir lashgari; azhang tajdini
Abstract
In this research, resistance and stress concentration on the seat structure were examined by changing the type of connection (tongue and groove connection , and double connection). platanus orientalis used to make wooden chairs. Moreover, we applied Ansys to calculate resistance and mechanical testing ...
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In this research, resistance and stress concentration on the seat structure were examined by changing the type of connection (tongue and groove connection , and double connection). platanus orientalis used to make wooden chairs. Moreover, we applied Ansys to calculate resistance and mechanical testing machine with a load of chairs 7/12 mm per minute to show the stress distribution on the chairs members . The results show that chairs by tongue and groove connection and having a simple structure and with bail , have more resistance and less stress distribution than a double chair with a simple structure and with indicating connection and the impact of the type of connection were significant on the chair resistance . The stress distribution shows that the maximum stress concentrations on the horizontal joints are visible . Finite element models show that the stress distribution is more uniform in chairs with tongue and groove connections.
Mechanical conversion of wood and wooden fittings
Hamid Reza Taghiyari; Mohammad Ghofrani; Farzad Arbabi ghamsari
Abstract
The present research project was carried out to find out tension-carrying capacity of corner miter V-joints in tensile and compression directions to be compared with those of dovetail joints. Variables included the type of wood-composites to produce the joints (MDF and particleboard), the number of V-nail ...
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The present research project was carried out to find out tension-carrying capacity of corner miter V-joints in tensile and compression directions to be compared with those of dovetail joints. Variables included the type of wood-composites to produce the joints (MDF and particleboard), the number of V-nail in each joint (2, 3, and 4 V-nails), and the height of V-nails (7 and 10 mm). Separate sets of joints were produced with and without polyvinyl acetate resin. Results demonstrated that the tension-carrying capacity under compression tension was significantly higher than those in the tensile tension. Moreover, MDF joints showed higher tension-carrying capacity in comparison to those made from particleboard. Joints with resin were significantly stronger than those without resin. Increase in the number of V-nails resulted in an improvement in the tension-carrying capacity in both directions. Based on the results of the present research project, it was concluded that V-nails are preferred to dovetail joints from different perspectives, including their lower production expenses, lack of need for an extra step to mill the joint so that joint bits be inserted into, fast and easy installation of V-joint in one-step process, as well as higher tension-carrying capacity. Based on the obtained results indicating the maximum tension-carrying capacity of 13.7 MPa and 28 MPa for V-nails without and with adhesive, respectively, it was concluded that 4 V-nails with 10 mm in height in MDF joint-members would be recommended for joints without resin. In case of joints with resin, MDF joint-members with 3 V-nails of 10 mm would provide the highest tension-carrying capacity for craftsmen and producers of furniture and cabinets.
Mechanical conversion of wood and wooden fittings
Mohammad Ghofrani; Zahra Mohammad Moradi; Saeed Khojasteh Khosro
Abstract
In present study the effect of different methods of applying transparent coatings on adhesion strength of coating in Walnut (Juglans regia), Maple (Acer velutinum) and Pine (Pinus eldarica) species was investigated. For this purpose, samples prepared with dimension of 200×100×20 mm and 8% ...
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In present study the effect of different methods of applying transparent coatings on adhesion strength of coating in Walnut (Juglans regia), Maple (Acer velutinum) and Pine (Pinus eldarica) species was investigated. For this purpose, samples prepared with dimension of 200×100×20 mm and 8% moisture content. Samples’ surfaces were sanded with 100, 120 and 180 grate sizes sandpaper significantly. Then after preparation wooden samples with sealer, their surfaces covered with clear and acid catalyzed transparent finish in separate process by using spray gun and applicator. Adhesion strength of coating was measured with Pull-Off method based on ASTM D4541 standard. Fluorescence microscopy test used for investigation coating penetration in spray gun and applicator method. Results showed that the method of applying coating on wooden surfaces has significantly affected adhesion strength, and highest adhesion strength between all samples, observed in samples coated with applicator method. Investigation of coating penetration indicated that applicator method had good penetration in wood substrate in comparison spray gun method. Highest differences in adhesion strength of coating between spray gun and applicator method were observed in Walnut and Maple’s samples. In general, highest adhesion strength of coating was found in Walnut samples covered with acid catalyzed transparent finish by using applicator method.
Mechanical conversion of wood and wooden fittings
Mostafa Poozesh; Hamid Reza Mansouri; babak Nosrati; Alireza Samzadeh
Abstract
This objective of this investigation was to modify and improve the water resistance of urea formaldehyde (UF) bonded particleboard adding Boric acid to the resin. Four levels (1, 2, 3 and 4) of boric acid based on the dry weight of the bonder were added to the UF resin. Then these mixtures were ...
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This objective of this investigation was to modify and improve the water resistance of urea formaldehyde (UF) bonded particleboard adding Boric acid to the resin. Four levels (1, 2, 3 and 4) of boric acid based on the dry weight of the bonder were added to the UF resin. Then these mixtures were used to produce particleboard. Physical and mechanical properties were examined according to the ASTM, D1013-04. The results showed that the using of this additive increased the water absorption and thickness swelling resistance after 2 and 24 hours immersion in water. Also using this additive increased the internal bonding of the boards after 24 hours after immersion in water, compared to the control sample but in the case of dry samples, the internal bonding decreased compared to the control sample. However it was not lower than standard value. As the Boric acid levels increased to 2 percent, bending strength of the samples was increased compare to the control sample and after this level it was decreased. Also with increasing the levels to 4 percent, modulus of elasticity of boards were increased compare to the control sample
Mechanical conversion of wood and wooden fittings
Hamideh Abdolzadeh; Ghanbar Ebrahimi; Mohammad Layeghi
Abstract
In this study, structural performance of corner joint reinforced by fiber reinforced polymers (FRP) at the area of maximum tension stress was investigated under diagonal tension loading. Therefore 1 to 3 layers of unidirectional woven Glass, Carbon and Kevlar fibers were used and hand ...
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In this study, structural performance of corner joint reinforced by fiber reinforced polymers (FRP) at the area of maximum tension stress was investigated under diagonal tension loading. Therefore 1 to 3 layers of unidirectional woven Glass, Carbon and Kevlar fibers were used and hand lay-up was done by vinyl ester and epoxy resins. Results of load-displacement curve at yield point exhibited capability of the reinforcing layers in preventing joint opening to some extent under load. However, failure was observed at the joint due to picking fibers from wood surface or members fracture near the interface when loading increased. Since the reinforced zones of the joints by FRP show the maximum shear stress, consequently the separation of fibers from wood surfaces increased at these locations. The adhesion of FRP layers to joint surface was not appropriate due to difficult process of layering at right angle of joints followed by probable formation of air bubbles. The results of assessing FRPs reinforcing behaviour indicated that application of vinyl ester in comparison with epoxy as matrix exhibited better performance. In addition, glass and carbon fibers showed better performance than Kevlar fibers as reinforcing agents.
Mechanical conversion of wood and wooden fittings
Mohammad Ghofrani; Mohammad Kahvand; Habib Noori
Abstract
This study was conducted to evaluate stress carrying capacity of miter corner joints fabricated with loose tenon with loose tenon under diagonal tension and compression loading. In this study, tests were carried out to determine the effects of dimension of loose tenon A (3.5 × 1 × 0.8 cm) ...
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This study was conducted to evaluate stress carrying capacity of miter corner joints fabricated with loose tenon with loose tenon under diagonal tension and compression loading. In this study, tests were carried out to determine the effects of dimension of loose tenon A (3.5 × 1 × 0.8 cm) and B (3 × 2 × 0.8 cm), type of adhesives (Polyvinyl acetate (PVA) and polyurethane (PU)) and most commonly used wood species in furniture industry including beech (Fagus orientalis L.) and fir (Abies alba). The results indicate the stress carrying capacity joints under compression is higher compared with that in tension. Stress carrying capacity joints constructed with dimension of loose tenon A was higher than that of those with B. Furthermore, the results have shown that wood species and type of adhesive had significant effect on the stress carrying capacity and performance of joints constructed of Beech wood and PU adhesive were stronger than joints made of Fir wood and PVA adhesive.
Physics and Mechanical Wood
Ehsan Haji rafiriha; Mehran Roohnia; Ahmad Jahan latibari; Ajang Tajidini
Abstract
The effect of lamination and adhesive coverage rate in layered products made from Poplar wood was studied The effect of lamination and adhesive coverage rate in layered products made from Poplar wood was studied by non-destructive free vibration test. 120 samples with nominal dimensions of 2.5×2.5×45 ...
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The effect of lamination and adhesive coverage rate in layered products made from Poplar wood was studied The effect of lamination and adhesive coverage rate in layered products made from Poplar wood was studied by non-destructive free vibration test. 120 samples with nominal dimensions of 2.5×2.5×45 cm without any obvious deficiencies were selected and free flexural vibration in free-free bars were performed for testing them. Samples were longitudinal cut in three thinner tangential layers and jointed together again using Poly Vinyl Acetate glue. The specimens were divided into four groups according to adhesive coverage rates, which one group was fully glued and 3 groups were carrying some glue deficiencies in different rates. Manipulated samples were tried again in above mentioned test. Results indicated that shear moduli compare to modulus of elasticity is a more sensitive parameter to evaluate glue efficiency in laminated beams but concerns remained due to blind points in flexural vibration nondestructive method.
Physics and Mechanical Wood
Hamideh Abdolzadeh; Ghanbar Ebrahimi; Mohammad Layeghi; Mehdi Ghasemieh; Seiad Ahmad Mirshokraei
Abstract
In this study, characteristics of wood-polymer fracture under mode I were investigated by double cantilever beam. In this regard, the properties of furfurylated specimens with three different levels of furfurylation (20%, 30% and 65%) were evaluated in both RL and TL systems. Results indicated that load-displacement ...
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In this study, characteristics of wood-polymer fracture under mode I were investigated by double cantilever beam. In this regard, the properties of furfurylated specimens with three different levels of furfurylation (20%, 30% and 65%) were evaluated in both RL and TL systems. Results indicated that load-displacement curves from mode I fracture specimens were changed by furfurylation so that it was much clear on curves of TL system. These changes not only included curve slope in elastic and proportional limit zones, but also fracture zone and initiation of crack growth were included . Furthermore furfurylation and raising its content on both systems and especially on TL one, caused to change in stress intensity factor, KIC , and critical energy release rate , GIC. In both systems GIC were highly increased by increasing of furfurylation contents. This criterion demonstrated that the wood- polymer showed much toughness under mode I fracture. Moreover, variation of KIC values due to furfurylation at both systems was different with that of GIC. At the RL system, ascending trend was observed at KIC and GIC values by increasing furfurylation levels. But at TL system, KIC was decreased by furfurylation and this criterion enhanced by increasing of furan polymer in the cell wall. Generally, results of this research show that fracture toughness of wood is highly affected by furfurylation process
Mechanical conversion of wood and wooden fittings
Mohammad Ghofrani; Hossein Hosseinkhani; Habib Rahimi dastjerdi; Saeid Khojasteh khosro; Parviz Amiri
Abstract
The objective of this study was to investigate the influence of hydrothermal treatment of walnut (Juglans regia) and caucasian elm (Zelkova Carpinifolia) wood species on their acoustic properties in radial and tangential directions. For this purpose, specimens were prepared with dimensions of 360 (L) ...
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The objective of this study was to investigate the influence of hydrothermal treatment of walnut (Juglans regia) and caucasian elm (Zelkova Carpinifolia) wood species on their acoustic properties in radial and tangential directions. For this purpose, specimens were prepared with dimensions of 360 (L) ×20 (R) ×20 (T) mm. Heat treatments in water medium were performed at 150ºC for 5 hours. Acoustic properties of specimens (specific modulus of elasticity, damping, acoustical coefficient, acoustical conversion efficiency and wave velocity) measured by free flexural vibration on a free-free bar method. Properties of treated specimens compared with control specimens. Result showed that hydrothermal treatment improved all acoustic properties of specimens. Acoustic properties of radial and tangential surfaces of walnut wood did not show significant difference; while in caucasian elm significant differences obtained between radial and tangential surface properties. Generally, better acoustic properties achieved in tangential direction of heat-treated Caucasian elm species. So, it is recommended as a suitable specimen to be used in making the sound-boards of musical instruments such as Iranian Santour and Xylophones and also resonator boxes.
Mechanical conversion of wood and wooden fittings
amir lashgari
Abstract
In this study, distribution pattern and tension concentration as well as failure prediction in dowel joint were analyzed. The effect of dowel diameter (6, 8, 10 mm) and wood type (Beech, Alder and white spruce) on tension resistance and bending moment were examined. The dimensions for making T-form joints ...
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In this study, distribution pattern and tension concentration as well as failure prediction in dowel joint were analyzed. The effect of dowel diameter (6, 8, 10 mm) and wood type (Beech, Alder and white spruce) on tension resistance and bending moment were examined. The dimensions for making T-form joints were 5×5×2/5 cm. Wooden dowel used in this research was carpinus betulus which accounts as the common dowel in market. Also, PVA was used in Joints. A total of 36Tshape samples comprising 9 combinations of the above factors in 4 replications were made. Tension resistance and bending moment were measured by mechanical test machine. For exertion strength due to analyzing the resistance loading speed equal to 1.25 mm/min were applied. Also, to analyze distribution pattern and tension concentration in affected joints, finite element method and ANSYS Software were used. According to the results of the simulation modeling, joint which endured the maximum tension complied with the real joints. Distribution of tension in the middle of the bending moment depth was greatest and tension in dowel joints was concentrated in impaired points.
Mechanical conversion of wood and wooden fittings
amir lashgari; Ahmad Jahan latibari
Abstract
The influence withdrawal strength and bending moment of mortise and tenon joint is investigated. Based on vast application of this type of different length of joint, the effect of tenon lengths (20 , 30, 40, mm) and wood type (beech, alder,spruce) These strength properties is investigated. 9 combination ...
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The influence withdrawal strength and bending moment of mortise and tenon joint is investigated. Based on vast application of this type of different length of joint, the effect of tenon lengths (20 , 30, 40, mm) and wood type (beech, alder,spruce) These strength properties is investigated. 9 combination of variables and total of 72 T-shape samples were tested at loading rate of 1.25 mm/min. The combination of variables significantly in fluences the load bearing capacity of joint. Joint produced with tenon lenghts of 30 mm and alder wood showed highest withdrawal strength and the joint produced at the tenon length and beech wood showed highest bending moment so this combination of variables is recommended.
Mechanical conversion of wood and wooden fittings
Mohssen Bahmani; Ghanbar Ebrahimi; Lyla Fathi
Abstract
Although doweled joints are vastly used in furniture frame, these are little. Information about its withdrawal strength. The intent of this study is both to obtain initial and primary information concerning the withdrawal strength of dowel pin and, as far as possible, to develop generalized expression ...
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Although doweled joints are vastly used in furniture frame, these are little. Information about its withdrawal strength. The intent of this study is both to obtain initial and primary information concerning the withdrawal strength of dowel pin and, as far as possible, to develop generalized expression to estimate its strength. In this study, the effect of dowel diameter from three levels of 6, 8 and 10 mm and two penetration depth levels of 9 and 12 mm on withdrawal strength has been investigated. The results show that the highest withdrawal strength belongs to dowel with diameter of 8 mm and penetration depth of 12mm. Based on statistical results the experimental model of has been obtained to predict withdrawal strength.
Composite wood products
Abdolah Najafi; Mehdi Faezipoor; Habibalah Khademi eslam; Saeid Kazemi; Amir homan Hamasi
Abstract
In this study flexural properties Wood-plastic composites(WPCs), the composites made from high density polyethylene(virgin, recycled and mix of them) and four types lignocellulosic fillers (wood sawdust, sanding of MDF, particleboard sawdust and rice hull) at %60 by weight fiber loadings were manufactured ...
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In this study flexural properties Wood-plastic composites(WPCs), the composites made from high density polyethylene(virgin, recycled and mix of them) and four types lignocellulosic fillers (wood sawdust, sanding of MDF, particleboard sawdust and rice hull) at %60 by weight fiber loadings were manufactured using a dry blend/hot press method. Nominal density and dimensions of the panels were 1g/cm3 and 35Î35Î1cm, respectively. After conditioning, flexural properties of the panels including flexural modulus and flexural strength were determined. The results show the flexural modulus and strength wood plastic composites containing sanding MDF and particleboard sawdust were higher than those made from other fillers. The flexural modulus and strength were affected by kind of high density polyethylene (virgin or recycled
Physics and Mechanical Wood
Habib Nori; Ahmad Jahan latibari; mohammad ghofrani
Abstract
Poplar trees are classified as a fast growth trees and because of short rotation period, and suitable technical properties, are considered by pulp and paper making industries. In this study, physical and anatomical properties and pulp and paper of three colons of poplar trees, populous Alba. L. colon ...
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Poplar trees are classified as a fast growth trees and because of short rotation period, and suitable technical properties, are considered by pulp and paper making industries. In this study, physical and anatomical properties and pulp and paper of three colons of poplar trees, populous Alba. L. colon 44.9, populous deltoids 69.55, and populous euramerican are investigated. The average fiber length of these three colons were 0.854, 1.148, 1.08 mm. respectively and their average dry specific gravity were 0.386, 0461, and 0.341 g/cm3, and also their average cellulose content were 50.5, 51.5, and 49.5 percent.For Kraft process cooking of the mentioned colons, three cooking time, 1, 2, and 3 hours, 17°C cooking heat, 25% sulfidity, and active alkali at 3 levels, 15, 17.5, and 20% were used. The results show that p. alba, colon 44.9, and p. deltoids colon 69.55 with using 20% A.A and 3 hours cooking time have 53% yield and 18 kappa number.
Mechanical conversion of wood and wooden fittings
Hossein Hosseinkhani; Abdolrahman Hosseinzadeh; Fardad Golbabaei; Abbas Fakhryan roghani; masoudreza habibi
Abstract
In order to establish a sawing pattern for small log of Iranian Poplar wood (Populus nigra), experimental specimens were prepared from fresh felled trees. All logs were cut in 230 cm, the length and two sawing patterns were used in order to saw and produce boards with 60 mm, nominal size in thickness. ...
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In order to establish a sawing pattern for small log of Iranian Poplar wood (Populus nigra), experimental specimens were prepared from fresh felled trees. All logs were cut in 230 cm, the length and two sawing patterns were used in order to saw and produce boards with 60 mm, nominal size in thickness. In this study the band saw both vertical and horizontal were used. The study provides considerable evidence that there is significant difference between two sawing patterns (live & traditional method) and live sawing gave significantly more yield and slabs than the other method Sawing pattern for each top diameter of logs have been also given. Since the cost of coating is not much in relation to the benefits, end coating of logs and storage is recommended.
