Influence of Joint Type Used in Core Layer on the Mechanical Properties of Blockboard Veneered with Different Wood Species

Document Type : Research Paper

Authors

1 M.Sc. Wood and Paper Science and Technology, University of Zabol, Zabol, I.R. Iran

2 Associate Professor, Department of Wood and Paper Science and Technology, University of Zabol, I.R. Iran

Abstract

This study evaluated the effects of end to end joint types of athel stripes at three level (end to end basic, end to end mitrated and end to end half lap joint) used in core layer veneered with three wood species (fir, beech and oak) and glued with three different ratio of melamine formaldehyde/urea formaldehyde resin (0:100, 25:75 and 50:50) on the bending strengths of bloakboard. According to analysis variance of data, it was determined that the type of joint had the effect on the modulus of rupture (MOR) and modulus of elasticity (MOE), significantly, so the panels having short stripes jointed with end to end half lap joint in core layer had the highest strength properties. The wood species of veneer and MF/UF resin ratio had the effect on the mechanical properties of panels, significantly. According to t-test results, the differences between the bending strengths perpendicular and parallel to the face/back veneer grain were significant. The MOR and MOE perpendicular to the face/back veneer grain ware higher than other. The panels manufactured with strips joint by end to end half lap joint in core layer veneered with fir glued with MF/UF ratio of 50:50 had the highest MOR and MOE perpendicular and parallel to the face/back veneer grained (48.48 N/mm2, 40.50 N/mm2, 9153 N/mm2 and 5962 N/mm2 respectively).
 

Keywords

References

 
[1]. Mantanis, G.I., and Birbilis, D. (2012). Experimental characterization of shrinkage and density of Tamarix aphylla wood. Cellulose Chemistry and Technology, 46(5-6): 369-373.
[2]. Laufenberg, T., Ayrilmis, N., and White, R. (2006). Fire and bending properties of blockboard with fire retardant treated veneers. Holz als Roh- und Werkstoff, 64: 137–143.
[3]. Tabarsa, T., and Farsi, M. (2003). Examine the possibility of making the beam layer (LVL) connections. Iranian Journal of Wood and Paper Industries, 1(3): 68-71.
[4]. Ozcifc, A. (2007). Effects of scarf joints on bending strength and modulus of elasticity to laminated veneer lumber (LVL). Building and Environment, 42: 1510–1514.
[5]. Bayatkashkoli, A., Shamsian, M., and Mansourfard, M. (2012). The effect of number of joints on bending properties of laminated lumber made from poplar (Populus nigra L.). Forest Studies in China, 14(3): 246–250.
[6]. Walford, G.B., (2000). Effect of finger length on finger-joint strength in radiata pine. In: World Conference on Timber Engineering, Jul.-Aug. 31-3 Whistler Resort, British Columbia, Canada, pp. 1-8.
[7]. Vassilios, V., Ioannis, B., and Sotorios, K. (2007). Effect of PVAc bonding on finger-joint strength of steamed and unsteamed beech wood (Fagus sylvatica). Journal of Applied Polymer Science, 103(3): 1665-1669.
[8]. Nazerian, M. (2013). The lamination influence on properties of agro-based particleboard. Wood Material Science and Engineering, 8(2): 129-138.
[9]. Norvydas, V., and Minelga, D. (2006). Strength and stiffness properties of furniture panels covered with different coatings. Materials Science, 12(4): 328-332.
[10]. Mao, A., Hassan, E.B., and Kim, M.G. (2013). Investigation of low mole ratio UF and UMF resins aimed at lowering the formaldehyde emission potential of wood composite boards.BioResources, 8(2): 2453-2469.
[11]. Standard Test Method for Flexural Properties of Sandwich Constructions. Annual Books of ASTM Standards, C 393-00. 2000.
[12]. Nazerian, M., and Dahmardeh Ghalehno, M. (2011). Technology of Plywood Manufacturing. Jihad – e –Daneshgahii Press. Tehran.
[13]. Fan, D.B., Li, J.Z., and Mao, A. (2006). Curing characteristics of low molar ratio urea formaldehyde resins. Journal of Adhesive and Interfaces, 7(4): 45-52.
[14]. Zhang, J., Wang, X., Zhang, S., Gao, Q., and Li, J. (2013). Effects of melamine addition stage on the performance and curing behavior of melamine-urea-formaldehyde (MUF) resin. BioResources, 8(4): 5500-5514.
[15]. Hse, C.Y. (2009). Development of melamine modified urea formaldehyde resins based on strong acidic pH catalyzed urea formaldehyde polymer. Forest Products journal, 59(5): 19-24.
[16]. Forest Products Laboratory. (2010). Wood handbook—Wood as an engineering material. General technical report FPL-GTR-190. Madison, WI: U.S. Department of Agriculture, Forest Service, Forest Products Laboratory. PP 508.
[17]. Wang, X., Ross, R.J., Brashaw, B.K., Verhey, S.A., Formsan, J.W., and Ericson, J.R. (2003). Flexural properties of laminated veneer lumber manufactured from ultrasonically rated red maple veneer. Forest Product Laboratory, FPL-RN-0288.
[18]. Kretschmann, D.E., and Green, D.W. (1996). Modeling moisture content- property relationships for clear southern pine. Wood and Fiber Science, 28(3): 320-337.
[19]. Mark, R.E. (1967). Cell Wall Mechanics of Tracheids, Yale University Press, New Haven, USA.
Forest and Wood Products
Volume 68, Issue 3 - Serial Number 3
October 2015
Pages 573-590

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