Study on long term creep of two different types of compressed wood sheets used in library shelves

Document Type : Research Paper

Authors

1 M.Sc. student, Wood Science and Technology Department, Faculty of Civil Engineering, Shahid Rajaee Teacher Training University, P.O. Box: 16785-163, Tehran, Iran

2 Associate Professor of Wood Science and Technology Department, Faculty of Civil Engineering, shahid Rajaee Teacher Training University, P.O. Box: 16785-163, Tehran, Iran

Abstract

In this study, the creep behaviors of composite panels used in library shelves were investigated. For this purpose, two types of wood-composite panels (medium density fiberboard and particleboard), and three types of covering including synthetic laminates, natural veneer, and without cove, and two types of wood joints (fixed and detachable) were used. Dimensions of the book-shelves were in actual shelf size, that is, 1,000 × 300 mm. Totally, 48 shelf specimens were prepared. For the creep test, a 23.5 kg loading level was applied in the center part of the shelves. Measurements on the creep behavior were carried out over 155 days at different intervals. Results indicated that the type of wood-composite as well as the type of veneer had statistically significant effect on the creep behaviors of panels. The lowest creep was observed in MDF panels. Moreover, those panels covered with natural veneer demonstrated significantly lower creep values. The type of joint also had a significant effect on the creeping behavior of the shelves, though not as conspicuous as the type of panels and veneers. Based on the results of the present research project, it is suggested that in order to increase the service life of library shelves it would be better to produce the shelves from MDF panels covered with natural veneers; these shelves should be fixed on supports.

Keywords


[1] Bodig, J. and Jayne, B.A., 1989. Mechanics of wood and wood composite. Translation by Ebrahimi G .Tehran, Tehran University Press, Iran, 680p.(In Persian).
[2] Aminian, H.and Hedayatollah, A., 1995. Investigation on the effect of moisture content on textural creep behavior of heart wood and sap wood of Caucasian oak. Master's thesis, Tarbiat Modares University, Faculty of Natural Resources, Noor. (In Persian).
[3] Doosthoseini, K., 2007. Wood composite materials manufacturing and applications, University of Tehran press. Tehran, Iran. (In Persian).
[4] Najafi, J., Mosavi, S.T. and Kord, B., 2012. Study on Flexural Creep Parameters of Overlayed Particleboard by Natural and Melaminated Veneers. Iranian Journal of Wood and Paper Industries, 3:119-128. (In Persian).
[5] Mohebby, B., Tavassoli, F. and Kazemi-Najafi, S., 2011. Mechanical properties of medium density fiberboard reinforced with metal and woven synthetic nets. European Journal of Wood and Wood Products, 69:199-206.
[6] Ebrahimi, M., Kazemie najafi, S. and Rabi, B.A., 2014. Effects of Relative Humidity and Temperature on Creep Parameters of Medium Density Fiberboard (MDF). Journal of Forest and wooden Product, 67: 47-357.
[7] Chen, T.Y. and Lin, J.S., 1997. Creep behavior of commercial wood based boards under long-term loading at room condition in Taiwan. Holz als roh – und werkstoff, 55: 371-376.
[8] Fernandes-Golfin, J.I. and Diez-barra, M.R., 1998. Long-term deformation of MDF panels under alternating humidity conditions. Wood Science and Technology, 32:33-41.
[9] Zhou, Y. G., Fushitani. M. and Kamdem. D. P., 2001. Bending Creep Behavior of Medium Density Fiberboard and Particleboard During Cyclic Moisture Changed. Wood and Fiber Science, 33: 609-617.
[10] Zhou, J., Hu, C., Hu, S., Yun, H., Jiang, G. and Zhang, S., 2012. Effects of temperature on the bending performance of wood-based panels. BioResources, 7: 3597-3606.
[11] Haygreen, J., Hall, H., Kuo-Ning, Y. and Sawicki, R., 1975. Studies of Flexural Creep Behavior in Particleboard under Changing Humidity Conditions. Wood and Fiber Science, 7: 74-90.
[12] Nemli, G. and Colakoglu, G., 2005. The influence of lamination technique on the properties of particleboard. Building and Environment, 40: 83-87.