Ultrasonic and Vibration Signals Processing for Computing Dynamic Modulus of Elasticity of Intact and Damaged Wood

Abstract

To effectively and quickly estimate the dynamic modulus of elasticity (MOE) of wood, ultrasonic and vibration test techniques are employed to measure the intact and damaged wood specimens. The ultrasonic and vibration signals in time domain are obtained respectively. Then, the time of flight is received by picking up the position of ultrasonic head wave and it is used to compute the dynamic MOE of wood. Simultaneously, the frequency response functions of wood are received by analyzing the frequency domain signals transformed from time domain using Fourier formulas, and they are used to pick up the intrinsic frequencies to calculate the dynamic MOE measured by vibration test. Finally, the correlations of dynamic MOE tested by these two methods are discussed. The research results show that it is feasible to estimate the dynamic MOE of wood via ultrasonic and vibration signal processing.