The thesis brings a research into the properties of different combinations of poplar and beech plywood in veneer boards with synthetic nets. We used 3 standard combinations for veneer boards - combo (every second layer is poplar with beech wood in between), sandwich (2 outer layers are made of beech wood with poplar layers between) and pure poplar (only poplar plywood is used). To these we added 2 types of glass fibre nets. The first was impregnated with melamine resin and was added on top of outer layers of veneer boards. A non-impregnated synthetic net, however, was added between the first and the second layer of the veneer boards. The main purpose of the research was to find the combination with the highest bending strength and the combination with the best strength/density ratio. Samples with 9 different combinations were measured for bending strength, elastic modulus and density in accordance with SIST EN 310, SIST EN 323 and SIST EN 326-1 standards. Tensile strength of the synthetic nets used was also measured. The results show that, due to the higher share of beech plywood, combo has the highest bending strength, while the most suitable strength/density ratio is in sandwich boards. Non-impregnated glass-fibre nets on the outer layers meanwhile reduce the bending strength of veneer boards in the joint, and melamine resin-impregnatednets on the outer layers improve bending strength of veneer boards only with sufficient sink or absorption.
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