Non-destructive evaluation for boreal tree species utilizing acoustic testing

Abstract

Standing trees pertain a level of uncertainty, in regards to yield and end-use. Thus, it may be feasible to analyse the forest, at the ground level, in order to allocate the timber resources accordingly. Through stress-wave propagation, a forester would attach a TreeSonic tester to the cambium in order to determine the wood quality. Furthermore, deviations and defects change the wave-speed (time-of-flight), where rot pockets, insect damage, and reaction wood can be detected by the change of TOF. This information is useful in respects of veneer logs, where the value is significantly higher compared to saw-logs or pulp. However, it is important to note that within the Boreal Forest, diameter-class largely influences product consideration. Thus, the broad objective of this thesis is to explore new market opportunities to give a competitive edge in the market. Therefore, using acoustic testing is a feasible non-destructive evaluation (NDE), in regard to efficiently assisting eFRI systems with wood quality. This is seen in the results, where the acoustic velocity values resulted significant. These values were used to calculate a predicted modulus of elasticity at 12%, which proved to have no significant difference from the actual MOE recorded from the destructive testing. This means that NDE can provide an accurate way to measure the “quality” of standing timber.