Determination of Shearing Properties for Tubular Pinewood under Torsion


In this study, tubular pinewood (Pinus sylvestris L.) specimens are tested and shear strain measurements are performed by applying torsion in z direction in the consideration of light weight aircraft engineering. The objective of this paper is to contribute and generate the nonlinear material model in terms of shear modulus presented with power functions under the consideration of nonlinear behavior of wood under torque. Strain gauge measurements are performed for the maximum shear stresses which develop on the tubular specimen, along the radial r(rin, rout), circumferential Φ(Φin, Φout) and z directions, in a point-wise manner. The data is gathered and examined for the determination of the local variations of empirical shear modulus functions on transversely isotropic surfaces of the specimens. The coordinate dependent shear modulus functions of GzΦ(r), GzΦ(Φ), GzΦ(z) are derived for GzΦ(r, Φ, z)as the function of r, Φ and z, respectively, by analyzing the gathered data. It is proposed to represent the shear modulus functions, GzΦ(Φ) and GzΦ(z) with the parabolic polynomials, and, to represent the shear modulus function GzΦ(r) with a linear equation.

Share and Cite:

Günay, E. and Uludogan, E. (2015) Determination of Shearing Properties for Tubular Pinewood under Torsion. Materials Sciences and Applications, 6, 48-59. doi: 10.4236/msa.2015.61007.

Conflicts of Interest

The authors declare no conflicts of interest.


[1] Wooster, W.A. (1949) A Textbook on Crystal Physics. Cambridge University Press, London.
[2] Bozorth, R.M. (1951) Ferromagnetism. Van Nostrand, New York.
[3] Turley, J. and Sines, G. (1971) The Anisotropy of Young’s Modulus Shear Modulus and Poisson’s Ratio in Cubic Materials. Journal of Physics D: Applied Physics, 4, 264-271.
[4] Saliklis, E.P. and Falk, R.H. (2000) Correlating Off-Axis Tension Tests to Shear Modulus of Wood-Based Panels. Journal of Structural Engineering, 126, 621-625.
[5] Salmén, L. (2004) Micromechanical Understanding of the Cell-Wall Structure. CR Biologies, 327, 873-880.
[6] Yoshihara, H. and Ohta, M. (1992) Stress-Strain Relationship of Wood in the Plastic Region. I. Examination of the Applicability of Plasticity Theories. Mokuzai Gakkaishi, 38, 759-763.
[7] Yoshihara, H. and Ohta, M. (1994) Stress-Strain Relationship of Wood in the Plastic Region. II. Formulation of the Equivalent Stress-Equivalent Plastic Strain Relationship. Mokuzai Gakkaishi, 40, 263-267.
[8] Yoshihara, H. and Ohta, M. (1995) Determination of the Shear Stress-Shear Strain Relationship of Wood by Torsion Tests. Mokuzai Gakkaishi, 41, 988-993.
[9] Yoshihara, H. and Ohta, M. (1997) Analysis of the Shear Stress/Shear Strain Relationships in Wood Obtained by Torsion Tests. Mokuzai Gakkaishi, 43, 457-463.
[10] Ramberg, W. and Osgood, W.R. (1943) Description of the Stress-Strain Curves by Three Parameters. National Advisory Committee for Aeronautics. US Government Printing Office, Washington DC, Tech. Note No. 902.
[11] O’Halloran, M.R. (1973) Curvilinear Stress-Strain Relationship for Wood in Compression. Ph.D. Dissertation, Colorado State University, Fort Collins.
[12] Foschi, R.O. (1974) Load-Slip Characteristics of Nails. Wood Science, 17, 69-77.
[13] Hu, J. (1990) Strength Analysis of Wood Single Bolted Joints. Ph.D. Thesis, University of Wisconsin, Madison.
[14] Werner, H. (1993) Bearing Capacity of Dowel-Type Wood Connections Accounting for the Influence of Relevant Parameters. Ph.D. Dissertation, Karlsruhe University, Karlsruhe.
[15] Davalos-Sotelo, R. and Pellicane, P.J. (1992) Bolted Connections in Wood under Bending/Tension Loading. Journal of Structural Engineering, 118, 999-1013.
[16] Patton-Mallory, M., Cramer, S.M., Smith, F.W. and Pellicane, P.J. (1997) Nonlinear Material Models for Analysis of Bolted Wood Connections. Journal of Structural Engineering, 123, 1063-1070.
[17] Patton-Mallory, M., Smith, F.W. and Pellicane, P.J. (1998) Modeling Bolted Connections in Wood: A Three-Dimensional Finite-Element Approach. Journal of Testing and Evaluation, 26, 115-124.
[18] Yoshihara, H., Ohsaki, H., Kubojima, Y. and Ohta, M. (1999) Applicability of the Iosipescu Shear Test on the Measurement of the Shear Properties of Wood. Journal of Wood Science, 45, 24-29.
[19] Ayina, O. and Morlier, P. (1998) Modelling the Behavior of Wood under a Constant Torque. Materials and Structures/Materiaux et Constructions, 31, 405-410.
[20] Tabiei, A. and Wu, J. (2000) Three-Dimensional Nonlinear Orthotropic Finite Element Material Model for Wood Composite Structures. Composite Structures, 50, 143-149.
[21] Magorou, L.L., Bos, F. and Rouger, F. (2002) Identification of Constitutive Laws for Wood-Based Panels by Means of an Inverse Method. Composites Science and Technology, 62, 591-596.
[22] Francescato, P., Pastor, J. and Enab, T. (2005) Torsional Behavior of a Wood-Based Composite Beam. Journal of Composite Materials, 39, 865-879.
[23] Dahl, K.B. and Malo, K.A. (2009) Nonlinear Shear Properties of Spruce Softwood: Numerical Analyses of Experimental Results. Composites Science and Technology, 69, 2144-2151.
[24] Dahl, K.B. and Malo, K.A. (2009) Linear Shear Properties of Spruce Softwood. Wood Science and Technology, 43, 499-525.
[25] Dahl, K.B. and Malo, K.A. (2009) Nonlinear Shear Properties of Spruce Softwood: Experimental Results. Wood Science and Technology, 43, 539-558.
[26] Liu, J.Y. and Ross, R.J. (2005) Relationship between Radial Compressive Modulus of Elasticity and Shear Modulus of Wood. Wood and Fiber Science, 37, 201-206.
[27] Gunay, E. and Konakll, S. (2004) The New Formed Shear Modulus Formulations for the Transversely Isotropic Fiber Composite Bars under Torsion Loading. Journal of the Faculty of Engineering and Architecture of Gazi University, 19, 1-12.
[28] Gunay, E. and Konakll, S. (2006) Formation of Shear Stress Equations for Transversely Isotropic Finite Length Bar under Torsion. Science and Engineering of Composite Materials, 13, 255-270.
[29] Uludogan, E. (2005) Coordinate Dependent Experimental Determination of Shear Modulus for Transversely Isotropic Composites by using Wood Torsion Specimens. MSc. Thesis, Gazi University, Institute of Science and Technology, Ankara.
[30] Gunay, E. and Uludogan, E. (2007) Experimental Determination of Shear Modulii Variation of Typical Transversely Isotropic Wood Specimens. Journal of Machine Design and Manufacturing, 9, 67-87.
[31] TQSM21 (1982) Torsion Testing Machine Manual. TecQuipment Ltd., Nottingham.
[33] Almemo (2003) Datalogger Unit Manual V5: Ahlborn Messund Regelungstechnik GmbH. Medewitzer, Straβe14, 02633 Gaussig, Berlin.
[35] Inan, M. (1970) Strength of Materials. Ofset Printing Ltd. Company, Istanbul.
[36] Gunay, E. and Orçan, Y. (2007) Experimental Investigation of the Mechanical Behavior of Solid and Tubular Wood Species under Torsional Loading. Turkish Journal of Engineering and Environmental Sciences, 31, 89-118.
[37] Gunay, E., Aygun, C. and Uludogan, E. (2012) Empirical Formulation of Shear Modulus Functions for Tubular Pinewood Specimens. 11th International Conference on Sustainable Energy Technologies (Set-2012), SET-2012-348, Vancouver, 2-5 September 2012, 1152-1162.
[38] Gibson, R.F. (1994) Principles of Composite Material Mechanics. McGraw-Hill Inc., Singapore City.
[39] Yoshihara, H. and Matsumoto, A. (2005) Measurement of the Shearing Properties of Wood by In-Plane Shear Test Using a Thin Specimen. Wood Science and Technology, 39, 141-152.

Copyright © 2023 by authors and Scientific Research Publishing Inc.

Creative Commons License

This work and the related PDF file are licensed under a Creative Commons Attribution 4.0 International License.