Effects of Grain Pattern on the Rolling Shear Properties of Wood in Cross-Laminated Timber
Abstract
:1. Introduction
2. Materials and Methods
2.1. Materials
2.2. Methods
3. Results and Discussion
3.1. Failure Modes
3.2. Rolling Shear Modulus and Strength
4. Theoretical Work
4.1. Mechanism of the Rolling Shear
4.2. Relationship of Grain and Rolling Shear Modulus
5. Conclusions
- (1)
- The apparent rolling shear modulus was the largest for the in-between grain-mode specimens (at a grain angle of 45°). However, it had the lowest values for parallel (0°) and right angle (90°) grain-mode specimens.
- (2)
- The rolling shear strength of the wood increased slightly with the aspect ratio because the stress concentration is very severe in small aspect ratio specimens.
- (1)
- The rolling shear moduli of 0° and 90° grain-mode of the wood were the same. This value can be called the pure rolling shear modulus.
- (2)
- The rolling shear moduli of the wood with angles other than 0° and 90° can be calculated from the pure rolling shear modulus and grain angle. Therefore, these moduli can be called the apparent rolling shear moduli.
- (3)
- Using 0° and 90° grain-mode specimens to determine the pure rolling shear modulus and strength of the wood is recommended.
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
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Group | Apparent Rolling Shear Modulus | Rolling Shear Strength | ||||
---|---|---|---|---|---|---|
Average (MPa) | COV | Sig 1 | Average (MPa) | COV | Sig | |
I-0 | 64.9 | 0.40 | ab | 1.26 | 0.38 | ab |
I-45 | 94.9 | 0.24 | a | 1.00 | 0.18 | a |
I-90 | 52.2 | 0.48 | b | 1.68 | 0.13 | b |
II-0 | 66.5 | 0.25 | ab | 1.74 | 0.12 | a |
II-45 | 154.5 | 0.57 | c | 1.38 | 0.39 | a |
II-90 | 79.5 | 0.19 | a | 1.67 | 0.17 | a |
III-0 | 51.6 | 0.43 | a | 1.44 | 0.11 | a |
III-45 | 184.1 | 0.29 | b | 1.73 | 0.16 | a |
III-90 | 96.5 | 0.16 | ac | 1.82 | 0.22 | a |
Average | 93.9 | 0.33 | - | 1.52 | 0.21 | - |
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Wu, G.; Zhong, Y.; Ren, H. Effects of Grain Pattern on the Rolling Shear Properties of Wood in Cross-Laminated Timber. Forests 2021, 12, 668. https://doi.org/10.3390/f12060668
Wu G, Zhong Y, Ren H. Effects of Grain Pattern on the Rolling Shear Properties of Wood in Cross-Laminated Timber. Forests. 2021; 12(6):668. https://doi.org/10.3390/f12060668
Chicago/Turabian StyleWu, Guofang, Yong Zhong, and Haiqing Ren. 2021. "Effects of Grain Pattern on the Rolling Shear Properties of Wood in Cross-Laminated Timber" Forests 12, no. 6: 668. https://doi.org/10.3390/f12060668
APA StyleWu, G., Zhong, Y., & Ren, H. (2021). Effects of Grain Pattern on the Rolling Shear Properties of Wood in Cross-Laminated Timber. Forests, 12(6), 668. https://doi.org/10.3390/f12060668