Acoustic and Elastic Properties of Modified Oak Wood

Abstract

This paper presents studies on acoustic and elastic properties of ammonia modified oak wood compared with parallel testing of unmodified oak control specimens. For evaluation ammonia-modification effects two testing devices were used – portable Timber Grader MTG (Brookhuis Micro-Electronics) and special ultrasonic strength meter, developed at Kaunas University of Technology. Variable physical-elastic-acoustic and size factors of specimens were focused on comparative specification the measurement accuracy and validation applicability of used instruments for testing specific wood properties. Essentially, getting reliable results responding actual wood anisotropy and local structural non-homogeneities was problematic when using tested devices separately. Even more complicated was reliable estimation of viscous-elastic changes and plasticization effects caused by thermo-chemical wood modification. Increased assurance was achieved when using both testers simultaneously.