Document Type : Research Paper

Authors

1 M.Sc., Wood and Paper Science and Technology, Karaj Branch, Islamic Azad University, Karaj, Iran

2 Associate Professor, Wood and Paper Science and Technology, Karaj Branch, Islamic Azad University, Karaj, Iran,

3 Professor, Wood and Paper Science and Technology, Karaj Branch, Islamic Azad University, Karaj, Iran

4 Associate Professor, Wood and Paper Science and Technology, Karaj Branch, Islamic Azad University, Karaj, Iran

Abstract

The effect of lamination and adhesive coverage rate in layered products made from Poplar wood was studied The effect of lamination and adhesive coverage rate in layered products made from Poplar wood was studied by non-destructive free vibration test. 120 samples with nominal dimensions of 2.5×2.5×45 cm without any obvious deficiencies were selected and free flexural vibration in free-free bars were performed for testing them. Samples were longitudinal cut in three thinner tangential layers and jointed together again using Poly Vinyl Acetate glue. The specimens were divided into four groups according to adhesive coverage rates, which one group was fully glued and 3 groups were carrying some glue deficiencies in different rates. Manipulated samples were tried again in above mentioned test. Results indicated that shear moduli compare to modulus of elasticity is a more sensitive parameter to evaluate glue efficiency in laminated beams but concerns remained due to blind points in flexural vibration nondestructive method.

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Main Subjects

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