Determination of the Ultrasonic Velocity on a Recent and Aged Pine Wood

Aging in wood is the inevitable modification of physical and mechanical properties due to deterioration caused by different factors such as organisms that destroy wood, photodegradation, weathering or long-term loading. During the wood degradation process, significant mass, stiffness and strength are lost. Therefore, it is relevant to monitor the wood decomposition process to guarantee the structural requirements in buildings. This research work aims to report the influence of degradation in wood due to deterioration through the use of ultrasonic measurements. Longitudinal and transverse ultrasonic velocities were calculated using the ultrasonic emission-transmission technique for aged and unaged Mexican pine (Pinus Strobus) wood. The experimental measurements were carried out using longitudinal and shear wave ultrasonic transducers with a center frequency of 1.0 MHz and 0.5MHz respectively. Scanning electron microscopy (SEM) was performed to establish a direct correlation with the behavior of the ultrasonic wave developed in naturally aged and unaged wood. Measurements revealed higher ultrasonic velocity values for unaged wood samples in longitudinal, tangential and radial directions compared to aged wood samples, but no significant differences were found in all other wood directions.