Longitudinal Vibration Test for the Use of a Circular Truncated Cone as a Log Model of Japanese Cedar

AbstractThis study examines a simple estimation method for the measurement of the mass of an on-site log through a vibration test. In this method, rather than the log itself, a cut end portion is weighed. For this purpose, the vibration method with additional mass (VAM) was applied to Sitka spruce (Picea sitchensis Carr.) circular truncated cones (model log) and Japanese cedar (Cryptomeria japonica D. Don) logs. Longitudinal vibration tests were performed on the circular truncated cones with/without an additional mass. Furthermore, the cut end portions of the circular truncated cones and logs were used as the virtual additional mass in the VAM. From the results of the vibration test using specimens with/without the concentrated mass, it is possible to estimate the mass of a circular truncated cone with 10% error by the VAM. The cut end portion of a circular truncated cone could be used as the virtual mass in the VAM. From the experimental and theoretical results, to maintain high estimation accuracy, the specimen length must not be too short as shown in our previous study for a specimen with constant cross-sectional shape. The cut end portion of the logs could be used for the virtual mass of the VAM.

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Young’s and shear moduli of glued laminated timber composed of different species obtained by a flexural vibration test

Holzforschung ◽

10.1515/hf-2011-0209 ◽

2012 ◽

Vol 66 (7) ◽

pp. 871-875 ◽

Cited By ~ 3

Author(s):

Yoshitaka Kubojima ◽

Mario Tonosaki

Keyword(s):

Elastic Constants ◽

Pinus Densiflora ◽

Flexural Vibration ◽

Japanese Cedar ◽

Picea Sitchensis ◽

Vibration Test ◽

Shear Moduli ◽

Glued Laminated Timber ◽

Flexural Vibration Test ◽

Lamination Theory

Abstract The applicability of the flexural vibration test to determine the elastic constants of glued laminated timber (GLT) composed of five wood species (ash, Fraxinus spaethiana Lingelsh.; balsa, Ochroma pyramidale Urban.; Japanese cedar, Cryptomeria japonica D. Don; Japanese red pine, Pinus densiflora Sieb. et Zucc.; Sitka spruce, Picea sitchensis Carr.) has been investigated. GLT models were prepared from four laminae with dimensions of 30 (R)×5 (T)×300 (L) mm3. The suitability of Japanese cedar for inner layers in GLTs was tested by flexural vibration test to determine the elastic constants of the laminae and the glued laminated timber. The Young’s and shear moduli were calculated by the Goens-Hearmon regression method based on the Timoshenko theory of bending (TGH method), and the results were compared with the estimated values based on the Young’s and shear moduli measured individually of each lamina. The simple lamination theory was found to be applicable for Young’s modulus but not to shear modulus. The result obtained based on the lamination theory from the shear strain energy was similar to that obtained by the TGH method.

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Effect of Specimen Width on the Measurement of the Off-Axis Young’s Modulus of Plywood Using the Longitudinal Vibration Test

Journal of the Society of Materials Science Japan ◽

10.2472/jsms.65.339 ◽

2016 ◽

Vol 65 (5) ◽

pp. 339-342

Author(s):

Hiroshi YOSHIHARA ◽

Taku KODAKA ◽

Masahiro YOSHINOBU

Keyword(s):

Young’S Modulus ◽

Young's Modulus ◽

Longitudinal Vibration ◽

Vibration Test ◽

Specimen Width

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Effect of specimen configuration and orthotropy on the Young’s modulus of solid wood obtained from a longitudinal vibration test

Holzforschung ◽

10.1515/hf-2020-0115 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Hiroshi Yoshihara ◽

Makoto Maruta

Keyword(s):

Young’S Modulus ◽

Transverse Direction ◽

Young's Modulus ◽

Longitudinal Vibration ◽

Longitudinal Direction ◽

Solid Wood ◽

Western Hemlock ◽

Width Ratio ◽

Vibration Test ◽

Length Width

AbstractYoung’s modulus in the longitudinal direction was measured by a longitudinal vibration (LV) test on western hemlock specimens with various length/width ratios. The effects of the configuration and orthotropy of the specimen on the measurement of Young’s modulus was investigated through subsequent finite element (FE) calculations. The experimental results suggested that Young’s modulus could not be obtained accurately when the length/width ratio of the specimen was in a certain range. The FE calculations revealed that Young’s modulus in the transverse direction and Poisson’s ratio in the length-width plane, as well as the length/width ratio, affected the Young’s modulus value. However, the results showed that when the length/width ratio of the specimen was larger than 10, Young’s modulus could be measured accurately with the LV test with a reduction in the effect of orthotropy.

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