NC State
BioResources
Roohnia, M., and Kohantorabi, M. (2015). "Dynamic methods to evaluate the shear modulus of wood," BioRes. 10(3), 4867-4876.

Abstract

There are different dynamic or static test methodologies for evaluating the shear and torsional moduli of wood. A preferred method is nondestructive, accurate, and standard. However, dynamic methods using conventional devices previously suggested for determining the orthotropic shear moduli of wood are neither accurate nor standard. Thus, a reliable method for evaluating the torsional modulus of wood through a torsional vibration test exists; however, it is not a standard test method at all. In this study, a standard methodology for refractory materials, ASTM C1548, was fitted to wood to meet the qualifications suggested in measuring the torsional vibration of an orthotropic material. A methodology based on Timoshenko’s advanced theory of free flexural vibration for orthotropic shear moduli was also defined to be compared to these reliable, standard procedures of torsional modulus evaluation. A promising conclusion was derived using improved computer-based instrumentation.
Download PDF