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22 records – page 1 of 3.

Composite Elements of Basalt Fibre Rods and Low Grade Glulam

https://research.thinkwood.com/en/permalink/catalogue76
Year of Publication
2014
Topic
Design and Systems
Mechanical Properties
Material
Glulam (Glue-Laminated Timber)
Application
Beams
Author
Raftery, Gary
Kelly, Fiona
Year of Publication
2014
Country of Publication
Canada
Format
Conference Paper
Material
Glulam (Glue-Laminated Timber)
Application
Beams
Topic
Design and Systems
Mechanical Properties
Keywords
Basalt Fiber Reinforced Polymer
Flexural
Low-Grade
Modulus of Rupture
Moisture
Testing
Pull-out Performance
Language
English
Conference
World Conference on Timber Engineering
Research Status
Complete
Notes
August 10-14, 2014, Quebec City, Canada
Summary
In recent years, increased focus has been placed on the development of timber as a natural renewable construction material. However, there exists significant potential for the development of environmentally friendly engineered structural elements by comb...
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Development of Cross-Laminated Timber (CLT) Products from Stress Graded Canadian Hem-Fir

https://research.thinkwood.com/en/permalink/catalogue2595
Year of Publication
2020
Topic
Design and Systems
Material
CLT (Cross-Laminated Timber)
Author
Wei, Peixing
Wang, Brad
Li, Zhong
Ju, Ronghua
Year of Publication
2020
Format
Journal Article
Material
CLT (Cross-Laminated Timber)
Topic
Design and Systems
Keywords
Hem-Fir
Modulus of Elasticity
Modulus of Rupture
Stress-Graded Lumber
Language
English
Research Status
Complete
Series
Wood Research
Summary
To explore the feasibility of hem-fir for CLT products, this work addressed the exploratory and pilot plant studies of hem-fir cross-laminated timber (CLT) products through mechanical tests. The hem-fir lumber was procured and then stress-graded based on dynamic modulus of elasticity (MOE). The resulted 5-ply prototype CLT products were then tested non-destructively and 3-ply pilot plant hem-fir CLT was tested destructively. The results showed that bending performance of hem-fir CLT panel can be predicted. Considering cost-competitiveness and end applications of hem-fir CLT products, the panel structure can be optimized based on the stress-graded data of hem-fir lumber.
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Durability of Structural Laminated Veneer Lumber in Outdoor Use

https://research.thinkwood.com/en/permalink/catalogue1567
Year of Publication
2016
Topic
Serviceability
Material
LVL (Laminated Veneer Lumber)
Author
Furuta, Naoyuki
Hirabayashi, Yasushi
Miyauchi, Teruhisa
Narita, Toshiki
Lee, Wonwoo
Year of Publication
2016
Country of Publication
Austria
Format
Conference Paper
Material
LVL (Laminated Veneer Lumber)
Topic
Serviceability
Keywords
Outdoor Exposure
Modulus of Rupture
Language
English
Conference
World Conference on Timber Engineering
Research Status
Complete
Notes
August 22-25, 2016, Vienna, Austria p. 1638-1645
Summary
This study aimed to investigate the durability of structural laminated veneer lumber (LVL) during outdoor use. We subjected LVL to outdoor exposure tests for 48 months; the tests were designed under the assumption of outdoor use such as temporary enclosure plates used in the construction field. The surfaces of the LVL specimens were painted, or preservatives were mixed with the adhesive in the glue line. Very slight changes were observed in the color of the specimens painted with solvent-born coatings. Modulus of rupture (MOR) in the flatwise direction after 48 months exposure was deteriorated to 60–80% of the initial value. The MOR in the edgewise direction was higher than that in the flatwise direction. The MOR values of the painted specimens were higher than those of the control specimens before 24 months of outdoor exposure, whereas after 36 months of exposure, the values of the painted specimens were almost equal to those of the control specimens. Shear strength retention was greater than MOR retention. We found that the face veneers of the specimens were deteriorated by outdoor exposure, whereas their inner layers were relatively sound.
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Durability of Structural Lumber Products after Exposure at 82C and 80% Relative Humidity

https://research.thinkwood.com/en/permalink/catalogue784
Year of Publication
2005
Topic
Mechanical Properties
Moisture
Material
LSL (Laminated Strand Lumber)
LVL (Laminated Veneer Lumber)
Solid-sawn Heavy Timber
Author
Green, David
Evans, James
Hatfield, Cherilyn
Byrd, Pamela
Organization
Forest Products Laboratory
Year of Publication
2005
Country of Publication
United States
Format
Report
Material
LSL (Laminated Strand Lumber)
LVL (Laminated Veneer Lumber)
Solid-sawn Heavy Timber
Topic
Mechanical Properties
Moisture
Keywords
Aspen
Douglas-Fir
Modulus of Elasticity
Modulus of Rupture
Southern Pine
Poplar
Relative Humidity
SPF
Temperature
Flexural Properties
Language
English
Research Status
Complete
Summary
Solid-sawn lumber (Douglas-fir, southern pine, Spruce– Pine–Fir, and yellow-poplar), laminated veneer lumber (Douglas-fir, southern pine, and yellow-poplar), and laminated strand lumber (aspen and yellow-poplar) were heated continuously at 82°C (180°F) and 80% relative humidity (RH) for periods of up to 24 months. The lumber was then reconditioned to room temperature at 20% RH and tested in edgewise bending. Little reduction occurred in modulus of elasticity (MOE) of solid-sawn lumber, but MOE of composite lumber products was somewhat reduced. Modulus of rupture (MOR) of solid-sawn lumber was reduced by up to 50% after 24 months exposure. Reductions in MOR of up to 61% were found for laminated veneer lumber and laminated strand lumber after 12 months exposure. A limited scope study indicated that the results for laminated veneer lumber in edgewise bending are also applicable to flatwise bending. Comparison with previous results at 82°C (180°F)/25% RH and at 66°C (150°F)/20% RH indicate that differences in the permanent effect of temperature on MOR between species of solid-sawn lumber and between solid-sawn lumber and composite lumber products are greater at high humidity levels than at low humidity levels. This report also describes the experimental design of a program to evaluate the permanent effect of temperature on flexural properties of structural lumber, with reference to previous publications on the immediate effect of temperature and the effect of moisture content on lumber properties.
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Effect of Knots and Slope of Grains on the Rolling Shear in Dimensional Timber Used in CLT Core Layers

https://research.thinkwood.com/en/permalink/catalogue1541
Year of Publication
2016
Topic
Mechanical Properties
Material
CLT (Cross-Laminated Timber)
Application
Beams
Author
Grandvuinet, Thibault
Muszynski, Lech
Year of Publication
2016
Country of Publication
Austria
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Application
Beams
Topic
Mechanical Properties
Keywords
Knots
Transverse Core Layer
Three Point Bending Test
Rolling Shear
MOR
Language
English
Conference
World Conference on Timber Engineering
Research Status
Complete
Notes
August 22-25, 2016, Vienna, Austria p. 1099-1104
Summary
The cross-laminated timber (CLT) technology is also perceived as a potential for utilization of lumber oflower grades and underused species, because the core layers perpendicular to the principle loading direction transferloads through rolling shear, which is not correlated to the grade of lumber. Current the product standard however specifies the minimum grade requirements for all lumber to be used as CLT laminations. In this study the effect of the presence of knots in the transverse core layer of CLT billets was examined in matched CLT samples where the heavy presence of knots in the transverse core layer was the only variable compared to knot free reference. All samples were tested as short-beams in three point bending and all failed in rolling shear in the transverse core layer. The presence of knots had no measurable effect on the shear capacity expressed as nominal MOR of the tested CLT beam samples
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Effect of Laminated Structure Design on Physical and Mechanical Properties of Laminated Bamboo Sliver Lumber

https://research.thinkwood.com/en/permalink/catalogue2491
Year of Publication
2019
Topic
Mechanical Properties
Design and Systems
Material
LVL (Laminated Veneer Lumber)
Other Materials
Application
Wood Building Systems

Effect of Laminated Structure Design on the Mechanical Properties of Bamboo-Wood Hybrid Laminated Veneer Lumber

https://research.thinkwood.com/en/permalink/catalogue1407
Year of Publication
2017
Topic
Mechanical Properties
Design and Systems
Material
LVL (Laminated Veneer Lumber)
Other Materials
Author
Chen, Fuming
Deng, Jianchao
Li, Xingjun
Wang, Ge
Smith, Lee
Shi, Sheldon
Publisher
Springer Berlin Heidelberg
Year of Publication
2017
Country of Publication
Germany
Format
Journal Article
Material
LVL (Laminated Veneer Lumber)
Other Materials
Topic
Mechanical Properties
Design and Systems
Keywords
Bamboo
Poplar
Analytical Model
Density
MOE
MOR
Shear Strength
Glue Lines
Loading Tests
Language
English
Research Status
Complete
Series
European Journal of Wood and Wood Products
ISSN
1436-736X
Summary
The effects of veneer orientation and loading direction on the mechanical properties of bamboo-bundle/poplar veneer laminated veneer lumber (BWLVL) were investigated by a statistical analysis method. Eight types of laminated structure were designed for the BWLVL aiming to explore the feasibility of manufacturing high-performance bamboo-based composites. A specific type of bamboo species named Cizhu bamboo (Neosinocalamus affinis) with a thickness of 6 mm and diameter of 65 mm was used. The wood veneers were from fast-growing poplar tree (Populus ussuriensis Kom.) in China. The bamboo bundles were obtained by a mechanical process. They were then formed into uniform veneers using a onepiece veneer technology. Bamboo bundle and poplar veneer were immersed in water-soluble phenol formaldehyde (PF) resin with low molecular weight for 7 min and dried to MC of 8–12 % under the ambient environment. All specimens were prepared through hand lay-up using compressing molding method. The density and mechanical properties including modulus of elasticity (MOE), modulus of rupture (MOR), and shearing strength (SS) of samples were characterized under loading parallel and perpendicular to the glue line. The results indicated that as the contribution of bamboo bundle increased in laminated structure, especially laminated on the surface layers, the MOE, MOR and SS increased. A lay-up BBPBPBB (Bbamboo, P-poplar) had the highest properties due to the cooperation of bamboo bundle and poplar veneer. A higher value of MOE and MOR was found for the perpendicular loading test than that for the parallel test, while a slightly higher SS was observed parallel to the glue line compared with perpendicular loading. Any lay-up within the homogeneous group can be used to replace others for obtaining the same mechanical properties in applications. These findings suggested that the laminated structure with high stiffness laid-up on the surface layers could improve the performance of natural fiber reinforced composites.
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Effect of Selected Factors on the Bending Deflection at the Limit of Proportionality and at the Modulus of Rupture in Laminated Veneer Lumber

https://research.thinkwood.com/en/permalink/catalogue2482
Year of Publication
2019
Topic
Mechanical Properties
Connections
Material
LVL (Laminated Veneer Lumber)

Effect of Selected Factors on the Bending Deflection at the Limit of Proportionality and at the Modulus of Rupture in Laminated Veneer Lumber

https://research.thinkwood.com/en/permalink/catalogue2494
Year of Publication
2019
Topic
Mechanical Properties
Design and Systems
Material
LVL (Laminated Veneer Lumber)
Application
Wood Building Systems

Effects of Component Ratio of the Face and Core Laminae on Static Bending Strenght Performance of Three-Ply Cross-Laminated Wood Panels with Sugi (Cryptomeria Japonica)

https://research.thinkwood.com/en/permalink/catalogue1468
Year of Publication
2006
Topic
Mechanical Properties
Material
CLT (Cross-Laminated Timber)
Author
Park, Han-Min
Fushitani, Masami
Publisher
Society of Wood Science and Technology
Year of Publication
2006
Country of Publication
United States
Format
Journal Article
Material
CLT (Cross-Laminated Timber)
Topic
Mechanical Properties
Keywords
Sugi
Lamina Thickness
Modulus of Elasticity
Modulus of Rupture
Proportional Limit Stress
Bending Strength
Language
English
Research Status
Complete
Series
Wood and Fiber Science
Summary
In order to improve the bending strength performance of three-ply laminated wood panels and use them as construction-grade panel materials, twelve types of three-ply cross-laminated wood panels whose percentages of core lamina thickness versus total lamina thickness were 33%, 50%, and 80% were made with sugi (Japanese cedar), and the effect of component ratio of the face and core laminae on their static bending strength performance was investigated. The moduli of elasticity (MOE), proportional limit stresses and moduli of rupture (MOR), perpendicular (C type) and parallel (C type) to the grain of face laminae markedly increased or decreased with increasing percentage of core lamina thickness. The percentages of core lamina thickness at which each strength property value of C type became equal to that of C type ranged from 65% to 80%. At each percentage of core lamina thickness, the MOE and proportional limit stress of C type were higher in C (45) specimens having perpendicular-direction lamina of 45° annual ring angle in the core than in C (90) specimens having perpendicular-direction lamina of 90° in the core, whereas there was little difference in MOR between C (45) specimens and C (90) specimens. For 45° specimens having the core lamina thickness from 60% to 70%, MOE as well as MOR parallel and perpendicular to the grain of face laminae exceeded the corresponding requirement values of structural plywood with 21.0-mm thickness specified in Japanese Agricultural Standards.
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22 records – page 1 of 3.