Pengujian Non Destruktif Gelombang Ultrasonik Pada Balok Tiga Jenis Kayu Tanaman Indonesia (Non Destructive Testing of Three Indonesian Plantations Wood Beam)

Abstract

'Jltrasonic-based methods of non destructive testing applied to wood have been mtenstvely developed during the last decade. There are two parameters used to evaluate of wood based on ultrasonic method, ultrasonic velocity and atenuation. The main objective of this research was to analyze ultrasonic velocity characteristics of wood beam. Three wood species were used in this research representing high, medium, and luw density. The beam specimen of (8 x 12 x 200) cm from tectona (Tectona grandts). manii wood (Maesopsis emtnii), and sengon (Paraserianthes falcatariaj were prepared in air dried condition. The ultrasonic wave propagation was measured by SybalesiDuo<ii> The dynamic stiffness (MOEd) was gained based on Chnstoffel equation formulating correlation ben* ten the ultrasonic velocities and density The results showed thai ultrasonic velocilv propagation decreased by increasing wood density between species On the other hand in same species higher wood density caused increase in ultrasonic velocity propagation Statistical analysis showed that no significant influence of vertical position of beam in tree (bottom, middle, and lop) on f'us and MOEd However, there was significant effect from measurement direction of wave propagation (longitudinal, radial, and tangential) length dimensions were influenced by ultrasonic velocity values in which those values decreased by increasing length dimension.