Document Type : Research Paper

Authors

1 Associate Professor, Department of Wood Technology and Engineering, Gorgan University of Agricultural Sciences and Natural Resources, Iran

2 - M.Sc., Graduate in Modification and Conservation of Wood, Department of Wood Technology and Engineering, Gorgan University of Agricultural Sciences and Natural Resources, Iran

Abstract

Radiography is a method of non-destructive for evaluating the quality of wood construction machinery in order to detect the defects due to natural degradation. The objective of this study was to investigate the assessment of Poplar (Populus deltoides) and beech (Fagus orientalis) wood defects arising from the decaying by using x-ray non-destructive method. In this study, for each of species, uncolored (no coating) and colored samples by acid catalyzed lacquers and nitrocellulose lacquers were used. Decay resistance test based on modified ASTM D1413 standard was performed. The decay process was done in the periods of 1, 2 and 3 months with use of Coriolus versicolor fungus at laboratory condition. After each of these periods, for the decay of the samples, x-ray imaging by using an imaging at the lateral, tangential and radial direction was done. Results of weight loss confirmed the presence of decay in the radiographic images. The results showed that after 1, 2 and 3 months of exposure to fungus, fungal degradation leads to weight loss in the painted and unpainted samples. So that, the weight loss caused by decay in beech was less than poplar samples. As well, the weight loss of unpainted was less than painted samples, which was also statistically significant. The x-ray results of unpainted and painted samples at the cross, tangential and radial directions indicate that decay has a more impact on beech in comparison to poplar wood structure. The study as well showed that the protective layer has partly a barrier for decay destruction in these samples.

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Main Subjects

-Ceraldi, C., Mormone, V. and Ermolli, E., 2001. Resistographic inspection of ancient timber structures for the evaluation or mechanical characteristics, Materials and Structures, 34:59-64.
-Franke, S. and Franke, B., 2014. X-Ray technology for the assessment of timber structures. Paper presented at the COST FP 1101 Workshop, Biel, Switzerland. 49-55.
-Fredriksson, M., Johansson, E. and Berglund, A., 2014. Rotating Pinus sylvestris sawlogs by projecting knots from x-ray computed tomography images onto a plane, BioResources, 9:816-827.
-Fu, G., 2005. Inspection and manitoring techniques for brigdes and civil structures, Woodhead Publishing in Materials. Cambridge. 100-114 pp.
-Hill, C., 2006. Wood Modification (Chemical, Thermal and Other Processes), School of Agricultural and Forest Sciences, University of Wales, Bangor – England, 261 pages.
-Kazemi Najafi, S., Najari, S., Pourtahmasi, K. and Karimi, A.N., 2008. 3D assessing of decay in oak using nondestructive ultrasonic technique, Journal of the Iranian natural resources, 61(3):723-432. (In Persian)
-Leone, R. and Breuil, C., 1998. Filamantus fungi can degrade aspen steryl esters and waxes, Journal of International Biodetrioration & Biodegradation. 41:133-137.
-Liu, Y., Gong, M., Li, L. and Chui, Y.H., 2014. Width effect on the modulus of elasticity of hardwood lumber measured by nondestructive evaluation techniques, Construction and Building Materials. 50:278-280.
-Madhoushi, M., Hashemi, S.M. and Behzad, M., 2008. Evaluation of influence of decay on dynamic and static moduli of elasticity in Iranian beech by using of NDT stress wave, J. Agric. Sci. Nat. Res., 15:176-183. (In Persian)
-Maeda, K., Ohta, M. and Momohara, I., 2011. Analysis of decay anisotrop by X-ray computer tomography, Pro Lingo, 7:18-25.
-Muszynski, L., 2009. Imaging wood plastic composites (WPCs): X-ray computed tomography, a few other promising techniques, and why we should pay attention, BioResource, 4:1210-1221.
-Nyström, J. and Kline, D.E., 2000. Automatic classification of compression wood in green southern yellow pine. Wood and Fiber Science, 32(3):301-310.
-Rinn, F., Schweingruber, F.H. and Schär, E., 1996. Resistograph and X-ray density charts of wood comparative evaluation of drill resistance profiles and X-ray density chart of different wood species. Holzforschung, 50:303-311.
-Saffarzadeh, M. and Masteri Farahani, M.R., 2013. Decay resistance of commercial plastic- pistachio twig flour composite with or pigment. Journal of wood & forest science and technology, 20:111-123. (In Persian)
-Spiridonova, R.B., Petkova, E., Georgieva, N., Yotova, L. and Spiridonov, I., 2007. Utilization of a chemical-mechanical pulp with improved properties from poplar wood in the composition of packing papers. BioResource, 2:34-40.
-Sousa, H.S., Branco, J.M. and Lourenço, P.B., 2014. Characterization of cross sections from old chestnut beams weakened by decay. International journal of architectural heritage, 8:436-451.
-Toyserkani, H., 2007. Non-destructive investigations. Isfahan, Isfahan University Jihad Press Center, 305 pages. (In Persian)
-Wang, L., Zhang, X., Xu, G., Xu, H. and Wu, J., 2014. Using lignin content, cellulose content, and cellulose crystallinity as indicators of wood decay in Juglans mandshurica Maxim. and Pinus koraiensis. BioResources, 9:6205-6213.
-Weiler, M., Missio, A.L., Darci A. Gatto, D.A. and William G., Güths, W.G., 2013. Nondestructive evaluation of wood decayed by xylophagous organisms. Materials Research, 16:1203-1213.
-Yokoyama, M., Gril, J., Matsuo, M., Yano, H., Sugiyama, J., Clair, B., Kubodera, S., Mistutani, T., Sakamoto, M., Ozaki, H., Imamura, M. and Kawai, M., 2009. Mechanical characteristics of aged Hinoki wood from Japanese historical buildings. Comptes Rendus Physique, 10:601-611.