Dynamic MOE of 55 species using small wood beams

Nondestructive impact-induced resonance vibrations and spectral analysis were used to determine the dynamic modulus of elasticity (MOE) of specimens from 45 hardwood and 10 softwood species. Relationships were obtained between air-dry specimens measuring 20 x 20 x 300 mm and small wood beams measuring 20 x 2 x 150 nun (nominal) cut from them. Dynamic longitudinal elastic modulus (E-L) and wave velocity (V-L) in the fiber direction were determined from the larger specimens. These were compared with the dynamic flexural elastic modulus (E-CB-cantilever mode) and the dynamic longitudinal elastic modulus (E-LB) with the corresponding wave velocity (V-BL) measured from the small beams. E-CB and E-LB were highly related to EL. V-LB was similarly related to V-L. The methods developed for small wood beams allow rapid evaluation of MOE from the outer wood of standing trees or they can be used for studies involving detailed localized evaluation of elastic wood properties.