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Mingjer Tsai - One of the best experts on this subject based on the ideXlab platform.
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the charring depth and charring rate of glued laminated timber after a standard fire exposure test
Building and Environment, 2009Co-Authors: Tehsin Yang, Songyung Wang, Mingjer TsaiAbstract:Abstract The purpose of this study was to investigate the charring depth, charring rate and heat release rate of glued laminated timbers (Glulams) made from five softwood species as determined by a standard fire test (CNS12514) and the cone calorimeter method. The results indicated that the average charring depth and charring rate of the bottom sides of specimens were higher than those of the lateral sides in the same specimen and after the same fire exposure conditions. The charring rates of most tested Glulam specimens could meet the Eurocode 5 and Australian standard 1720.4. The charring rate in all Glulam specimens showed a decreasing order as follows: Taiwania>Japanese cedar>China fir>Douglas fir>Southern pine Glulam. Generally, the charring rate of Glulam specimens decreases with an increase of density. The correlation coefficient (r=0.53) for the relationship between the charring rate and density value was not high. However, a high correlation (r=0.88–0.89) between the charring rate/density and density was found in further analysis. The average heat release rate and the total heat release of tested specimens were (in decreasing order): Taiwania>Japanese cedar>China fir.
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Effect of fire exposure on the mechanical properties of glued laminated timber
Materials & Design, 2009Co-Authors: Tehsin Yang, Songyung Wang, Mingjer Tsai, Ching-yuan Lin, Ying-ji ChuangAbstract:Abstract The purpose of this study was to investigate the effect of fire exposure on the mechanical properties of glued laminated timbers (Glulams) made from five softwood species as determined by a standard fire test (CNS12514). The results indicated that the static bending properties of Glulam decreased with an increasing fire exposure time. After fire exposure tests, the retention rates of MOE (modulus of elasticity) and MOR (modulus of rupture) of all tested Glulams were 61.0–92.7% and 42.0–75.9%, respectively. Compared to the control specimens without fire exposure, the compression strength and the shear strength of tested Glulams after fire exposure did not show any significant difference.
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Temperature distribution within glued laminated timber during a standard fire exposure test
Materials & Design, 2009Co-Authors: Tehsin Yang, Songyung Wang, Mingjer Tsai, Ching-yuan LinAbstract:Abstract The purpose of this study was to investigate the temperature distribution within glued laminated timbers (Glulams) made from five softwood species as determined by a standard fire exposure test (CNS12514). The results reveal that the temperature within the middle section of tested Glulam increased with increasing fire exposure time. After a fire exposure of 30 min and 45 min, the average temperature in the center of middle section for tested Glulams (with a cross-section of 266 mm in depth × 190 mm in width) ranged from 27.5–28.3 °C to 29.5–33.2 °C; whereas, the average temperature for tested Glulams (with a cross-section of 266 mm in depth × 140 mm in width) increased rapidly (from 32.3–51.1 °C to 39.1–89.3 °C) with an increasing exposure time and a decreasing cross-section. It was also found that the temperature in the center of the middle section increased slower than that in the right side or left side of a Glulam middle section. The temperature within Glulams (78 mm from the surface) remained constant without significant influence of fire exposure time according to CNS 12514. It can also be observed that equations developed by the Swiss Federal Institute of Technology give a closer calculation for the temperature development in tested Glulams with heat flux from three sides.
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evaluation of the mechanical properties of douglas fir and japanese cedar lumber and its structural Glulam by nondestructive techniques
Construction and Building Materials, 2008Co-Authors: Tehsin Yang, Songyung Wang, Chengjung Lin, Mingjer TsaiAbstract:Abstract The objectives of this study were to investigate the effects of the configuration of the lamina on the bending properties of Glulam made from Douglas-fir and Japanese cedar lumber. By using a visual grading method according to CNS 14631 and nondestructive evaluation techniques (including the ultrasonic wave technique, transverse vibration test and static bending test), lamina having both higher dynamic MOE and static MOE were chosen for the outside layers, in order to manufacture homogeneous and heterogeneous grade structural Glulam lamina, with higher strength properties. The degrees of correlation, obtained from the different nondestructive testing methods, were then analyzed. The results indicated that the DMOEv, DMOEt and MOE values for both Douglas-fir and Japanese cedar lumber showed a decreasing order as follows: construction grade > standard grade > utility grade. It was also found that the transverse vibration test is a better nondestructive method of evaluating sawn lumber. The different configurations of the lamina within Glulam can be used to fabricate Glulams with different grades of bending strengths. The predicted values of Glulam E b(sp) , were higher than those of the experimental values E b(sc) . Moreover, the value of E b(sc) increased linearly with an increasing MOE of the outside layers of lamina ( e 3 ).
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Effect of laminate configuration on the modulus of elasticity of Glulam evaluated using a strain gauge method
Journal of Wood Science, 2007Co-Authors: Tehsin Yang, Songyung Wang, Mingjer Tsai, Chengjung Lin, Far-ching LinAbstract:The purpose of this study was to measure the strain of Glulam laminae by affixing a strain gauge at the central axis of the lateral face in order to determine the effect of the configuration of the Glulam. Japanese cedar and southern pine were used in the study. The strain and stress of the laminae during the bending test were recorded, and the modulus of elasticity ( MOE ) was calculated. The influence of the MOE of the adhesive layers was also considered. Results showed that the MOE of the laminated elements increased as its specific gravity increased, although the specific gravity was not the only factor evaluated. The MOE of Glulam ( E _bsg) measured by the strain gauge method was very close to the observed MOE of Glulam ( E _b) and a significant linear relationship was identified. The MOE ( e ) of laminae measured by the strain gauge method was very close to that determined ( E ) under the “free condition” before bonding. The difference between the modified MOE ( E _bsa) and E _bsg was not significant. The MOE of Glulams made of heterogeneously graded lumbers were about 23% and 31% larger than the average MOE of their laminae for Japanese cedar and southern pine, respectively. The actual neutral axis was just below the longitudinal center line. It shifted slightly within the proportional limit range and moved downward when the load increased.
Tehsin Yang - One of the best experts on this subject based on the ideXlab platform.
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Effects of ACQ preservative treatment on the mechanical properties of hardwood Glulam
European Journal of Wood and Wood Products, 2012Co-Authors: Tehsin Yang, Songyung Wang, Chih-hsien Lin, Far-ching LinAbstract:In dieser Studie werden die mechanischen Eigenschaften von mit ACQ behandeltem Brettschichtholz aus drei verschiedenen Laubholzarten untersucht. Dabei wurden auch zwei zerstörungsfreie Methoden, nämlich Ultraschall- und Längsschwingungsmessung, verwendet. Die Ergebnisse zeigten, dass der dynamische und der statische Elastizitätsmodul (MOE) von Schnittholz mit zunehmender ACQ-Schutzmittelaufnahme abnahmen. Die ANOVA-Analyse ergab keine signifikanten Unterschiede zwischen den MOE Werten der unbehandelten und der behandelten Prüfkörpergruppe. Daneben hat sich gezeigt, dass die Biegefestigkeit bei Brettschichtholz aus Roteiche am geringsten beeinträchtigt war. Die Scherfestigkeit von Brettschichtholz zeigte ähnliche Ergebnisse. Delaminierungsprüfungen ergaben bei allen untersuchten Brettschichtholzgruppen keine Delaminierungen. The purpose of this study is to examine the mechanical properties of ACQ-treated Glulam made from three hardwood lumbers. Two nondestructive methods, ultrasonic wave and tap tone method, were also used in this study. The results showed that the dynamic MOE and static MOE of lumbers decreased with increased ACQ preservative retention. ANOVA showed no significant difference in the MOE values of Glulam between untreated and ACQ-treated group. However, it was also found that Glulam made from red oak lumbers had the highest bending strength retention ratio. The shear strength of the Glulam also showed similar results. Finally, no delaminating was found in all Glulams after the specimens under soaked and boiled delamination tests.
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the charring depth and charring rate of glued laminated timber after a standard fire exposure test
Building and Environment, 2009Co-Authors: Tehsin Yang, Songyung Wang, Mingjer TsaiAbstract:Abstract The purpose of this study was to investigate the charring depth, charring rate and heat release rate of glued laminated timbers (Glulams) made from five softwood species as determined by a standard fire test (CNS12514) and the cone calorimeter method. The results indicated that the average charring depth and charring rate of the bottom sides of specimens were higher than those of the lateral sides in the same specimen and after the same fire exposure conditions. The charring rates of most tested Glulam specimens could meet the Eurocode 5 and Australian standard 1720.4. The charring rate in all Glulam specimens showed a decreasing order as follows: Taiwania>Japanese cedar>China fir>Douglas fir>Southern pine Glulam. Generally, the charring rate of Glulam specimens decreases with an increase of density. The correlation coefficient (r=0.53) for the relationship between the charring rate and density value was not high. However, a high correlation (r=0.88–0.89) between the charring rate/density and density was found in further analysis. The average heat release rate and the total heat release of tested specimens were (in decreasing order): Taiwania>Japanese cedar>China fir.
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Effect of fire exposure on the mechanical properties of glued laminated timber
Materials & Design, 2009Co-Authors: Tehsin Yang, Songyung Wang, Mingjer Tsai, Ching-yuan Lin, Ying-ji ChuangAbstract:Abstract The purpose of this study was to investigate the effect of fire exposure on the mechanical properties of glued laminated timbers (Glulams) made from five softwood species as determined by a standard fire test (CNS12514). The results indicated that the static bending properties of Glulam decreased with an increasing fire exposure time. After fire exposure tests, the retention rates of MOE (modulus of elasticity) and MOR (modulus of rupture) of all tested Glulams were 61.0–92.7% and 42.0–75.9%, respectively. Compared to the control specimens without fire exposure, the compression strength and the shear strength of tested Glulams after fire exposure did not show any significant difference.
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Temperature distribution within glued laminated timber during a standard fire exposure test
Materials & Design, 2009Co-Authors: Tehsin Yang, Songyung Wang, Mingjer Tsai, Ching-yuan LinAbstract:Abstract The purpose of this study was to investigate the temperature distribution within glued laminated timbers (Glulams) made from five softwood species as determined by a standard fire exposure test (CNS12514). The results reveal that the temperature within the middle section of tested Glulam increased with increasing fire exposure time. After a fire exposure of 30 min and 45 min, the average temperature in the center of middle section for tested Glulams (with a cross-section of 266 mm in depth × 190 mm in width) ranged from 27.5–28.3 °C to 29.5–33.2 °C; whereas, the average temperature for tested Glulams (with a cross-section of 266 mm in depth × 140 mm in width) increased rapidly (from 32.3–51.1 °C to 39.1–89.3 °C) with an increasing exposure time and a decreasing cross-section. It was also found that the temperature in the center of the middle section increased slower than that in the right side or left side of a Glulam middle section. The temperature within Glulams (78 mm from the surface) remained constant without significant influence of fire exposure time according to CNS 12514. It can also be observed that equations developed by the Swiss Federal Institute of Technology give a closer calculation for the temperature development in tested Glulams with heat flux from three sides.
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evaluation of the mechanical properties of douglas fir and japanese cedar lumber and its structural Glulam by nondestructive techniques
Construction and Building Materials, 2008Co-Authors: Tehsin Yang, Songyung Wang, Chengjung Lin, Mingjer TsaiAbstract:Abstract The objectives of this study were to investigate the effects of the configuration of the lamina on the bending properties of Glulam made from Douglas-fir and Japanese cedar lumber. By using a visual grading method according to CNS 14631 and nondestructive evaluation techniques (including the ultrasonic wave technique, transverse vibration test and static bending test), lamina having both higher dynamic MOE and static MOE were chosen for the outside layers, in order to manufacture homogeneous and heterogeneous grade structural Glulam lamina, with higher strength properties. The degrees of correlation, obtained from the different nondestructive testing methods, were then analyzed. The results indicated that the DMOEv, DMOEt and MOE values for both Douglas-fir and Japanese cedar lumber showed a decreasing order as follows: construction grade > standard grade > utility grade. It was also found that the transverse vibration test is a better nondestructive method of evaluating sawn lumber. The different configurations of the lamina within Glulam can be used to fabricate Glulams with different grades of bending strengths. The predicted values of Glulam E b(sp) , were higher than those of the experimental values E b(sc) . Moreover, the value of E b(sc) increased linearly with an increasing MOE of the outside layers of lamina ( e 3 ).
Songyung Wang - One of the best experts on this subject based on the ideXlab platform.
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Effects of ACQ preservative treatment on the mechanical properties of hardwood Glulam
European Journal of Wood and Wood Products, 2012Co-Authors: Tehsin Yang, Songyung Wang, Chih-hsien Lin, Far-ching LinAbstract:In dieser Studie werden die mechanischen Eigenschaften von mit ACQ behandeltem Brettschichtholz aus drei verschiedenen Laubholzarten untersucht. Dabei wurden auch zwei zerstörungsfreie Methoden, nämlich Ultraschall- und Längsschwingungsmessung, verwendet. Die Ergebnisse zeigten, dass der dynamische und der statische Elastizitätsmodul (MOE) von Schnittholz mit zunehmender ACQ-Schutzmittelaufnahme abnahmen. Die ANOVA-Analyse ergab keine signifikanten Unterschiede zwischen den MOE Werten der unbehandelten und der behandelten Prüfkörpergruppe. Daneben hat sich gezeigt, dass die Biegefestigkeit bei Brettschichtholz aus Roteiche am geringsten beeinträchtigt war. Die Scherfestigkeit von Brettschichtholz zeigte ähnliche Ergebnisse. Delaminierungsprüfungen ergaben bei allen untersuchten Brettschichtholzgruppen keine Delaminierungen. The purpose of this study is to examine the mechanical properties of ACQ-treated Glulam made from three hardwood lumbers. Two nondestructive methods, ultrasonic wave and tap tone method, were also used in this study. The results showed that the dynamic MOE and static MOE of lumbers decreased with increased ACQ preservative retention. ANOVA showed no significant difference in the MOE values of Glulam between untreated and ACQ-treated group. However, it was also found that Glulam made from red oak lumbers had the highest bending strength retention ratio. The shear strength of the Glulam also showed similar results. Finally, no delaminating was found in all Glulams after the specimens under soaked and boiled delamination tests.
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the charring depth and charring rate of glued laminated timber after a standard fire exposure test
Building and Environment, 2009Co-Authors: Tehsin Yang, Songyung Wang, Mingjer TsaiAbstract:Abstract The purpose of this study was to investigate the charring depth, charring rate and heat release rate of glued laminated timbers (Glulams) made from five softwood species as determined by a standard fire test (CNS12514) and the cone calorimeter method. The results indicated that the average charring depth and charring rate of the bottom sides of specimens were higher than those of the lateral sides in the same specimen and after the same fire exposure conditions. The charring rates of most tested Glulam specimens could meet the Eurocode 5 and Australian standard 1720.4. The charring rate in all Glulam specimens showed a decreasing order as follows: Taiwania>Japanese cedar>China fir>Douglas fir>Southern pine Glulam. Generally, the charring rate of Glulam specimens decreases with an increase of density. The correlation coefficient (r=0.53) for the relationship between the charring rate and density value was not high. However, a high correlation (r=0.88–0.89) between the charring rate/density and density was found in further analysis. The average heat release rate and the total heat release of tested specimens were (in decreasing order): Taiwania>Japanese cedar>China fir.
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Effect of fire exposure on the mechanical properties of glued laminated timber
Materials & Design, 2009Co-Authors: Tehsin Yang, Songyung Wang, Mingjer Tsai, Ching-yuan Lin, Ying-ji ChuangAbstract:Abstract The purpose of this study was to investigate the effect of fire exposure on the mechanical properties of glued laminated timbers (Glulams) made from five softwood species as determined by a standard fire test (CNS12514). The results indicated that the static bending properties of Glulam decreased with an increasing fire exposure time. After fire exposure tests, the retention rates of MOE (modulus of elasticity) and MOR (modulus of rupture) of all tested Glulams were 61.0–92.7% and 42.0–75.9%, respectively. Compared to the control specimens without fire exposure, the compression strength and the shear strength of tested Glulams after fire exposure did not show any significant difference.
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Temperature distribution within glued laminated timber during a standard fire exposure test
Materials & Design, 2009Co-Authors: Tehsin Yang, Songyung Wang, Mingjer Tsai, Ching-yuan LinAbstract:Abstract The purpose of this study was to investigate the temperature distribution within glued laminated timbers (Glulams) made from five softwood species as determined by a standard fire exposure test (CNS12514). The results reveal that the temperature within the middle section of tested Glulam increased with increasing fire exposure time. After a fire exposure of 30 min and 45 min, the average temperature in the center of middle section for tested Glulams (with a cross-section of 266 mm in depth × 190 mm in width) ranged from 27.5–28.3 °C to 29.5–33.2 °C; whereas, the average temperature for tested Glulams (with a cross-section of 266 mm in depth × 140 mm in width) increased rapidly (from 32.3–51.1 °C to 39.1–89.3 °C) with an increasing exposure time and a decreasing cross-section. It was also found that the temperature in the center of the middle section increased slower than that in the right side or left side of a Glulam middle section. The temperature within Glulams (78 mm from the surface) remained constant without significant influence of fire exposure time according to CNS 12514. It can also be observed that equations developed by the Swiss Federal Institute of Technology give a closer calculation for the temperature development in tested Glulams with heat flux from three sides.
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evaluation of the mechanical properties of douglas fir and japanese cedar lumber and its structural Glulam by nondestructive techniques
Construction and Building Materials, 2008Co-Authors: Tehsin Yang, Songyung Wang, Chengjung Lin, Mingjer TsaiAbstract:Abstract The objectives of this study were to investigate the effects of the configuration of the lamina on the bending properties of Glulam made from Douglas-fir and Japanese cedar lumber. By using a visual grading method according to CNS 14631 and nondestructive evaluation techniques (including the ultrasonic wave technique, transverse vibration test and static bending test), lamina having both higher dynamic MOE and static MOE were chosen for the outside layers, in order to manufacture homogeneous and heterogeneous grade structural Glulam lamina, with higher strength properties. The degrees of correlation, obtained from the different nondestructive testing methods, were then analyzed. The results indicated that the DMOEv, DMOEt and MOE values for both Douglas-fir and Japanese cedar lumber showed a decreasing order as follows: construction grade > standard grade > utility grade. It was also found that the transverse vibration test is a better nondestructive method of evaluating sawn lumber. The different configurations of the lamina within Glulam can be used to fabricate Glulams with different grades of bending strengths. The predicted values of Glulam E b(sp) , were higher than those of the experimental values E b(sc) . Moreover, the value of E b(sc) increased linearly with an increasing MOE of the outside layers of lamina ( e 3 ).
Yusuf Sudo Hadi - One of the best experts on this subject based on the ideXlab platform.
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TECHNICAL NOTE: SUBTERRANEAN TERMITE RESISTANCE OF SMOKED GLUED LAMINATED LUMBER MADE FROM FAST GROWING TREE SPECIES IN INDONESIA
Wood and Fiber Science, 2016Co-Authors: Yusuf Sudo Hadi, Muh. Yusram Massijaya, Mulyani Efendi, Arinana Arinana, Gustan PariAbstract:Abstract . The purpose of this research was to determine the resistance of smoked glued laminated lumber (Glulam) against subterranean termites ( Coptotermes curvignathus Holmgren), using Japanese standard JIS K1571-2004. Glulam was made from fast-growing wood species, namely Acacia mangium (mangium), Maesopsis eminii (manii), and Falcataria moluccana (sengon). The Glulam was constructed with either the same species for all layers or mangium as the face and back layers and a core layer of manii or sengon. Glulams were smoked for 15 or 30 days using smoke of mangium wood, and Glulam preserved with imidacloprid and untreated Glulam were prepared for comparative purposes. Mangium smoke was found to predominantly produce acetic acid, cyclobutanol, phenolic compounds, and other polycyclic aromatic hydrocarbons that improved Glulam resistance to subterranean termite attack. Smoked Glulam had the same resistance to subterranean termites as imidacloprid-preserved Glulam and was much more resistant than untreated Glulam. Glulam smoked for 15 days had the same resistance as that smoked for 30 days Keywords : Smoked Glulam, Fast-growing tree species, Subterranean termite , GC-MS, preservation .
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Resistance of Smoked Glued Laminated Lumber to Subterranean Termite Attack
Forest Products Journal, 2016Co-Authors: Yusuf Sudo Hadi, Muh. Yusram Massijaya, Mulyani Efendi, Gustan Pari, ArinanaAbstract:Abstract Timber from plantation forest mostly contains sapwood, and the heartwood part has a lot of juvenile wood, which has low resistance to attack by subterranean termites (Coptotermes curvignathus). Wood smoke created through pyrolysis contains numerous polycyclic aromatic hydrocarbons that could prevent termite attack. Three-layer glued laminated lumber (Glulam) was created using either the same wood species (mangium [Acacia mangium], manii [Maesopsis eminii], or sengon [Falcataria moluccana]) for all layers or a combination of mangium as the face and back layers and a core layer of manii or sengon. Glulam samples were exposed to smoke from mangium wood for 15 days, preserved with imidacloprid, or left untreated. All Glulams were tested against subterranean termites according to the Indonesian standard. Gas chromatography revealed that smoke from mangium predominantly contained acetic acid, cyclobutanol, and phenolic compounds. Smoked Glulam was more resistant to subterranean termite attack than untr...
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Glulam Properties of Fast-growing Species Using Mahogany Tannin Adhesive
North Carolina State University, 2015Co-Authors: Andi Sri Rahayu Diza Lestari, Yusuf Sudo Hadi, Dede Hermawan, Adi SantosoAbstract:Manufacturing glued laminated timber (Glulam) can help overcome the limited availability of large-sized timber, and the use of bio-adhesives may resolve environmental problems associated with synthetic adhesives containing high formaldehyde contents. Tannin adhesive is a bio-adhesive that can be used as alternative glue in the manufacture of Glulam. The purpose of this study was to determine the physical and mechanical properties of Glulam made with mahogany (Swietenia sp.) tannin adhesive and wood from three fast-growing species, namely pine (Pinus merkusii), jabon (Anthocephalus cadamba), and sengon (Falcataria moluccana). Glulam (3 cm × 6 cm × 120 cm in thickness, width, and length, respectively) was manufactured with three layers of lamina. The physical and mechanical properties of the Glulams were tested based on relevant standards. The results showed that pine Glulam fulfilled the standard for the modulus of rupture and modulus of elasticity, while sengon Glulam met the standard for shear strength. In the delamination test, sengon Glulam was resistant to immersion in cold water and hot water. All Glulams had low formaldehyde emission levels and therefore fulfilled the standard requirements. The results showed that the tannin adhesive from mahogany bark was equal in quality to methylene diphenyl di-isocyanate for Glulam manufacturing
R.z. Yang - One of the best experts on this subject based on the ideXlab platform.
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An experimental study on shear strength of glubam
Construction and Building Materials, 2017Co-Authors: Yan Xiao, Y. Wu, Jian Li, R.z. YangAbstract:Abstract Glued-laminated bamboo (glubam) is a new type of structural material, which is developed as a potential alternative to the glued-laminated lumber or Glulam. Similar to modern timber structures, connecting the glubam elements using steel joints requires a good understanding of the shear behavior of the material. In this study, glubam boards with three different bamboo strip (or fiber) configurations are manufactured and studied. Three types of glubam boards were manufactured and tested, including glubam with two bidirectional fiber arrangements at the ratios of 4:1 and 1:1, respectively, in the two orthogonal directions, and also the unidirectional fiber arrangement. The shear strengths in different loading conditions are experimentally investigated, following testing specifications for conventional wood. The study found that the in-plane shear strength values follow a normal distribution well, whereas the out-of-plane shear strength values can be statistically expressed by Weibull distribution. Based on the test results, the out-of-plane shear strengths and the in-plane shear strengths of glubam are studied, and the characteristic values and the design values are suggested. The relationship between the out-of-plane shear strength and the bidirectional ratio of bamboo strip (or fiber) has also been obtained with reasonably good correlation to the test results.