Can the impulse propagation speed from cross-section tomography explain the conditioned density of wood?

Tomography is a wave-based technique used to depicture tree cross-sections; specifically, impulse tomography uses data given by the passage of impulse waves, which were primarily influenced by density, modulus of elasticity, and moisture content of wood. The influence of wood characteristics on various kinds of waves has been extensively studied, allowing the establishment of statistical correlations between wave behavior and wood properties. In this context, the relationship between impulse speed from cross-section tomography and conditioned density that was obtained on diametrical sample by X-ray densitometry was analyzed using logs of three tree species with different densities that were air dried to 12 % moisture content. For each species, means from 5 mm length intervals of conditioned density profile graph (ρ12%) and impulse speed distribution graph (S12%) on the same diametrical sample are used to fit models. Joining data from all species, the exponential model $$ \ln \rho_{12\% } = - 4.32822 + 1.67894 *\ln S_{12\% } $$lnρ12%=-4.32822+1.67894∗lnS12% was obtained with correlation coefficient of 0.85 and highly significant parameters. The results indicate that conditioned density could be explained by impulse speed on the cross-section, but research is necessary to make a useful tool out of it.

[1]  Almir Sales,et al.  Relationship between density and ultrasonic velocity in Brazilian tropical woods. , 2006, Bioresource technology.

[2]  Michael F. Ashby,et al.  On the mechanics of balsa and other woods , 1982, Proceedings of the Royal Society of London. A. Mathematical and Physical Sciences.

[3]  P. Hietz,et al.  Wood density and its radial variation in six canopy tree species differing in shade-tolerance in western Thailand , 2009, Annals of botany.

[4]  S. Smulski,et al.  Relationship of Stress Wave- and Static Bending-Determined Properties of Four Northeastern Hardwoods , 1991 .

[5]  Paulo Estevão Cruvinel,et al.  Wood Density Determination by X- and Gamma-Ray Tomography , 2002 .

[6]  Fleur Longuetaud,et al.  Measuring wood density by means of X-ray computer tomography , 2009, Annals of Forest Science.

[7]  Bert Masschaele,et al.  High-resolution proxies for wood density variations in Terminalia superba. , 2011, Annals of botany.

[8]  P. Niemz,et al.  Determination of Young’s and shear moduli of common yew and Norway spruce by means of ultrasonic waves , 2007, Wood Science and Technology.

[9]  Arno Burmester,et al.  Zusammenhang zwischen Schallgeschwindigkeit und morphologischen, physikalischen und mechanischen Eigenschaften von Holz , 1965, Holz als Roh- und Werkstoff.

[10]  G. R. Johnson,et al.  Relationships of density, microfibril angle, and sound velocity with stiffness and strength in mature wood of Douglas-fir , 2010 .

[11]  R. Trianoski,et al.  Wood anatomical characteristics and paper resistance index of Schizolobium parahyba (Vell.) Blake from experimental plant. , 2012 .

[12]  Giovanni Nicolotti,et al.  Application and comparison of three tomographic techniques for detection of decay in trees , 2003 .

[13]  J. Ilic.  Relationship among the dynamic and static elastic properties of air-dry Eucalyptus delegatensis R. Baker , 2001, Holz als Roh- und Werkstoff.

[14]  J. Ilic,et al.  Dynamic MOE of 55 species using small wood beams , 2003, Holz als Roh- und Werkstoff.

[15]  Voichita Bucur,et al.  Acoustics of Wood , 1995 .

[16]  R. Evans,et al.  Prediction of MOE of eucalypt wood from microfibril angle and density , 2003, Holz als Roh- und Werkstoff.

[17]  K. Niklas,et al.  The Influence of Rays on the Transverse Elastic Anisotropy in Green Wood of Deciduous Trees , 2001 .

[18]  Adriano Wagner Ballarin,et al.  Application of X-Ray technique in nondestructive evaluation of eucalypt wood , 2008 .

[19]  J. Ilic.  Variation of the dynamic elastic modulus and wave velocity in the fibre direction with other properties during the drying of Eucalyptus regnans F. Muell , 2001, Wood Science and Technology.

[20]  Ryogo Nakada,et al.  Cell wall structure and wood properties determined by acoustics—a selective review , 2003, Holz als Roh- und Werkstoff.