Moisture-dependent orthotropic elasticity of beech wood

Elastic material properties are one of the most important material characteristics in mechanical modelling. Wood with distinctively different properties in the longitudinal, radial and tangential directions exhibits a strong moisture-dependent material characteristic in the elastic range. In order to characterise beech wood as an orthotropic material, all of the independent elastic properties were determined at different moisture conditions. These characteristic properties have never been determined before as a function of moisture content yet are vital to the field of wood modelling. All elastic parameters, except for some Poisson’s ratios, show a decrease in stiffness with increasing moisture content. In comparison to available literature references at a moisture content of ω ≈ 12%, the identified values were of the same order of magnitude. The determined material properties can be used to investigate the mechanical behaviour of beech wood structures including different moisture conditions.

[1]  F. Kollmann,et al.  Technologie des Holzes und der Holzwerkstoffe , 1955 .

[2]  Z. Hashin,et al.  A method to produce uniform plane-stress states with applications to fiber-reinforced materials , 1978 .

[3]  K. A. Malo,et al.  Nonlinear shear properties of spruce softwood: experimental results , 2009, Wood Science and Technology.

[4]  K. A. Malo,et al.  Linear shear properties of spruce softwood , 2009, Wood Science and Technology.

[5]  S. Diot,et al.  Minimization of Friction Influence on the Evaluation of Rheological Parameters From Compression Test: Application to a Forging Steel Behavior Identification , 2009 .

[6]  Peter Niemz,et al.  Untersuchungen zur Bestimmung der Poissonschen Konstanten an Fichtenholz , 2008, Holz als Roh- und Werkstoff.

[7]  R. Hearmon,et al.  The effect of grain direction on the Young's moduli and rigidity moduli of beech and sitka spruce , 1941 .

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

[9]  J. Stamer.  Elastizitätsuntersuchungen an Hölzern , 1935 .

[10]  H. Hörig,et al.  Anwendung der Elastizitätstheorie anisotroper Körper auf Messungen an Holz , 1935 .

[11]  Jozsef Bodig,et al.  Mechanics of Wood and Wood Composites , 1982 .

[12]  H. Neuhaus.  Über das elastische Verhalten von Fichtenholz in Abhängigkeit von der Holzfeuchtigkeit , 2007, Holz als Roh- und Werkstoff.

[13]  D. Guitard,et al.  Modèles prévisionnels de comportement élastique tridimensionnel pour les bois feuillus et les bois résineux , 1987 .

[14]  V. Bucur,et al.  Elastic constants for wood by an ultrasonic method , 1984, Wood Science and Technology.

[15]  P. Niemz,et al.  Three-dimensional elastic behaviour of common yew and Norway spruce , 2008, Wood Science and Technology.

[16]  J. Mier.  Fracture Processes of Concrete , 1997 .

[17]  J. Szalai,et al.  Measurement of standard and off-axis elastic moduli and Poisson’s ratios of spruce and yew wood in the transverse plane , 2010, Wood Science and Technology.

[18]  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.

[19]  Kenneth Olofsson,et al.  An Analysis of Rolling Shear of Spruce Wood by the Iosipescu Method , 2000 .