The composition influence of the cross laminated timber panels on the bending strength and the modulus of elasticity was researched. 6 panels having 3 differently thick layers, and 2 panels with 5 layers were tasted. It was found out that the thickness of the layers did not influence the bending strength or the modulus of elasticity; the higher number of layers improved the quality in transverse direction, and deteriorated it in the longitudinal direction. The bending strength was higher at edgewise bending as compared to the flatwise bending in any direction. The modulus of elasticity was higher at flatwise bending longitudinal direction and at the edgewise bending in transverse direction. All the data were verified mathematically on the basis of theoretical evaluations. The calculated results were very similar to the test results. It came to deviations at the bending strength of the longitudinal flatwise loaded test. The panel properties were highly depending on the wood quality and the quality of the laminated joints. Testing the samples the supposition was confirmed that the cross laminated timber had the proper attributes for construction building.
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