scholarly journals Effect of Additional Mass on the Apparent Young’s Modulus of a Wooden Bar by Longitudinal Vibration

BioResources ◽  
2014 ◽  
Vol 9 (3) ◽  
Author(s):  
Yoshitaka Kubojima ◽  
Youki Suzuki ◽  
Mario Tonosaki
2010 ◽  
Vol 26-28 ◽  
pp. 936-939
Author(s):  
Li Zhang ◽  
Ying Cheng Hu

In this paper, the poplar LVL was reinforced with multilayer fiberglass mesh. The reinforcing effect of adding position of fiberglass mesh on improving the static MOE was studied. And three different nondestructive testing (NDT) methods, such as the longitudinal transmission method, longitudinal vibration method and flexural vibration method (out-plane and in-plane), were used to test the dynamic properties of the reinforced poplar LVL. The correlation analysis was implemented between the dynamic Young’s modulus and the static MOE of the reinforced poplar LVL. It can be concluded that the three NDT methods are useful for predicting the MOE of reinforced LVL, but the flexural and longitudinal vibration methods had better accuracy to estimate the MOE.


2011 ◽  
Vol 380 ◽  
pp. 348-351 ◽  
Author(s):  
Jiang Chang ◽  
Xue Gong ◽  
Zhi Hui Sun

In this paper the vibration testing and Fast Fourier Transform(FFT) analysis detection on the basis of nondestructive testing method were analyzed. The dynamic Young’s modulus of the regeneration pre-sensitized offset plate were obtained by using the nondestructive testing methods, including the dynamic Young’s modulus by longitudinal vibration method, the dynamic Young’s modulus by out-plane flexural vibration method, and the dynamic Young’s modulus by in-plane flexural vibration method. The linear correlativity was investigated between the dynamic Young’s modulus and the modulus of elasticity(MOE) for the regeneration pre-sensitized offset plate.The linear correlations between the dynamic Young’s modulus and the MOE were good. So it is feasible to predict and analyze the plate mechanical properties put forward the nondestructive testing method of key mechanical performance parameters.


2005 ◽  
Vol 33 (4) ◽  
pp. 11937 ◽  
Author(s):  
DR Petersen ◽  
RE Link ◽  
Y Kubojima ◽  
M Tonosaki ◽  
H Yoshihara

2020 ◽  
Vol 34 (26) ◽  
pp. 2050232
Author(s):  
Xiaofei Lei ◽  
Peng Chen ◽  
Heping Hou ◽  
Shanhui Liu ◽  
Peng Liu

In this paper, a novel composite acoustical hyperstructure of Bragg structure with local resonator is investigated theoretically for discussing the scattering performance of longitudinal vibration wave, its bandgaps are calculated using the established mathematical model. For confirming the veritable existence of bandgap and verifying the correctness of established mathematical model, the transmission spectrum of composite acoustical hyperstructure is also studied using finite-element method, and comparing the vibration transmission spectrum with bandgaps, the results indicate that the established theoretical model can correctly predict longitudinal wave bandgaps. Moreover, the bandgaps and modes shapes are calculated and compared with an unalloyed Bragg structure for probing the dispersion mechanics of composite acoustical hyperstructure, it turned out that local resonator can add one bandgap at the base of Bragg structure and the total bandgaps can be broadened. Further, for discussing the effect of spring of local resonator on bandgaps, bandgap of local resonator with different spring is calculated, the results showed that the total width of BG is larger when Young’s modulus is 1E and 16E, the total width are 772.48 and 774.30 Hz, respectively; as Young’s modulus is 0.5E and 2E, the width of BG are lower, 753.79 and 754.23 Hz, respectively. In view of longitudinal vibration wave inducing structural distortion and vibration energy conversion, the dynamic properties of composite acoustical hyperstructure are studied via strain energy density, the results indicate that reaction formation of local resonator can dissipate strain energy, when the local resonator is not activated (or waveless along with Bragg structure), un-dissipation strain energy.


2010 ◽  
Vol 129-131 ◽  
pp. 588-591
Author(s):  
Li Zhang ◽  
Ying Cheng Hu

In this paper, the poplar LVL was reinforced with monolayer fiberglass mesh. The reinforcing effect of lay angle between the weft of fiberglass mesh and the veneer grain was studied. And three different nondestructive testing (NDT) methods, such as the longitudinal transmission method, longitudinal vibration method and flexural vibration method (out-plane and in-plane), were used to test the dynamic Young’s modulus of the reinforced poplar LVL. The correlativity was investigated between the dynamic Young’s modulus and the static MOE of the reinforced poplar LVL. The reinforcing effect was best when the lay angle of fiberglass mesh was 30°. And the flexural vibration method and longitudinal vibration method had better accuracy to estimate the static MOE.


2014 ◽  
Vol 534 ◽  
pp. 012064
Author(s):  
Sushil Phadke ◽  
Bhakt Darshan Shrivastava ◽  
Ashutosh Mishra ◽  
N Dagaonkar

Holzforschung ◽  
2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Hiroshi Yoshihara ◽  
Makoto Maruta

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.


Sign in / Sign up

Export Citation Format

Share Document