Multiscale Stochastic Modeling of the Elastic Properties of Strand-Based Wood Composites
Publication: Journal of Engineering Mechanics
Volume 138, Issue 7
Abstract
This paper introduces a novel modeling approach for wood composites using concepts of numerical homogenization employed in synthetic composites. It describes a multiscale model based on a unit cell that incorporates both the wood and resin phases for simulating structural composite lumber made of strands. In this approach, constant resin thickness and strand geometry, elastic properties of constituents, and perfect bonding between wood and resin are assumed. The multiscale modeling is composed of two steps. The first step estimates the effective elastic properties of a unit cell based on the numerical homogenization with periodic boundary conditions. The second step consists of a macroscopic finite element structural analysis of a beam (assembly of several unit cells) under three-point bending. Random distribution of strand orientation that may be encountered in an actual composite beam is introduced at this stage. Results indicate a significant influence of the resin. The first step of the approach provides an initial illustration when comparing effective properties of unit cells with different resin volume fractions and/or elastic properties. The resin decreases the Young’s modulus of the unit cell in the fiber direction while strengthening the transverse and shear moduli depending on the contrast between the resin and wood properties. The final results obtained for the beam show that the bending modulus decreases with increasing resin content, which is a combined effect of the micromechanical phenomena. The key contribution of this paper to modeling wood composites is the addition of the resin phase to a numerical model and inclusion of random distribution of strand orientation.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
The authors thank Xavier Mulet, visiting student scholar from ENSAM, France, for his contribution to the numerical studies reported in this paper. Financial support from the Natural Sciences and Engineering Research Council of Canada (NSERC) through a collaborative research and development grant with FPInnovations is gratefully acknowledged.
References
Arwade, S. A., Clouston, P. L., and Winans, R. (2009). “Measurement and stochastic computational modeling of the elastic properties of parallel strand lumber.” J. Eng. Mech.JENMDT, 135(9), 897–905.
Bejo, L., and Lang, E. M. (2004). “Simulation based modeling of the elastic properties of structural composite lumber.” Wood Fiber Sci., 36(3), 395–410.WFSCD4
Blomquist, R. F. (1983). Adhesive bonding of wood and other structural materials, Materials Research Laboratory, Pennsylvania State University, University Park, PA.
Cha, J. K., and Pearson, R. G. (1994). “Stress-analysis and prediction in 3-layer laminated veneer lumber—response to crack and grain angle.” Wood Fiber Sci., 26(1), 97–106.WFSCD4
Clouston, P. L. (2007). “Characterization and strength modeling of parallel-strand lumber.” Holzforschung, 61(4), 394–399.HOLZAZ
Clouston, P. L., and Lam, F. (2001). “Computational modeling of strand-based wood composites.” J. Eng. Mech.JENMDT, 127(8), 844–851.
Clouston, P. L., and Lam, F. (2002). “A stochastic plasticity approach to strength modeling of strand-based wood composites.” Compos. Sci. Technol., 62(10–11), 1381–1395.CSTCEH
Fan, M., and Enjily, V. (2009). “Structural properties of oriented wood strand composite: Effect of strand orientation and modeling prediction.” J. Eng. Mech.JENMDT, 135(11), 1323–1330.
Gereke, T., Malekmohammadi, S., Nadot-Martin, C., Dai, C., Ellyin, F., and Vaziri, R. (2010). “Morphological and mechanical characterization of parallel strand lumber.” Proc., 10th Pacific Rim Bio-Based Composites Symp., Banff, AB, Canada.
Green, D. W., Winandy, J. E., and Kretschmann, D. E. (1999). “Mechanical properties of wood.” Wood Handbook—Wood as an engineering material, U.S. Department of Agriculture, Forest Service, Forest Products Laboratory, Madison, WI.
Halpin, J. C., and Kardos, J. L. (1976). “The Halpin-Tsai equations: A review.” Polym. Eng. Sci., 16(5), 344–352.PYESAZ
Herakovich, C. T. (1998). Mechanics of fibrous composites, John Wiley & Sons, New York.
Jeulin, D., and Ostoja-Starzewski, M. (2001). Mechanics of random and multiscale microstructures, Springer, New York.
Kanit, T., Forest, S., Mounoury, V., and Jeulin, D. (2003). “Determination of the size of the representative volume element for random composites: Statistical and numerical approach.” Int. J. Solids Struct., 40(13–14), 3647–3679.IJSOAD
Kanit, T., N’Guyen, F., Forest, S., Jeulin, D., Reed, M., and Singleton, S. (2006). “Apparent and effective physical properties of heterogeneous materials: Representativity of samples of two materials from food industry.” Comput. Methods Appl. Mech. Eng., 195(33–36), 3960–3982.CMMECC
Konnerth, J., Gindl, W., and Muller, U. (2007). “Elastic properties of adhesive polymers. I: Polymer films by means of electronic speckle pattern interferometry.” J. Appl. Polym. Sci., 103(6), 3936–3939.JAPNAB
Michel, J. C., Moulinec, H., and Suquet, P. (1999). “Effective properties of composite materials with periodic microstructure: A computational approach.” Comput. Methods Appl. Mech. Eng., 172(1–4), 109–143.CMMECC
Shaler, S. M., and Blankenhorn, P. R. (1990). “Composite model prediction of elastic-moduli for flakeboard.” Wood Fiber Sci., 22(3), 246–261.WFSCD4
Stürzenbecher, R., Hofstetter, K., Schickhofer, G., and Eberhardsteiner, J. (2010). “Development of high-performance strand boards: Multiscale modeling of anisotropic elasticity.” Wood Sci. Technol.WOSTBE, 44(2), 205–223.
Terada, K., Hori, M., Kyoya, T., and Kikuchi, M. (2000). “Simulation of the multi-scale convergence in computational homogenization approaches.” Int. J. Solids Struct., 37(16), 2285–2311.IJSOAD
Torquato, S. (2002). Random heterogeneous materials, Springer, New York.
Triche, M. H., and Hunt, M. O. (1993). “Modeling of parallel-aligned wood strand composites.” For. Prod. J.FPJOAB, 43(11–12), 33–44.
Xia, Z., Zhang, Y., and Ellyin, F. (2003). “A unified periodical boundary conditions for representative volume elements of composites and applications.” Int. J. Solids Struct., 40(8), 1907–1921.IJSOAD
Information & Authors
Information
Published In
Journal of Engineering Mechanics
Volume 138 • Issue 7 • July 2012
Pages: 791 - 799
Copyright
© 2012. American Society of Civil Engineers.
History
Received: Feb 11, 2011
Accepted: Dec 12, 2011
Published online: Jun 15, 2012
Published in print: Jul 1, 2012
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.