Due to special needs and requirements, more and more adjustments are needed in the production of wood panel composites. Either within the product's structure or in manufacturing technology. The purpose of the graduation thesis, is to adapt the structure, so that the final product is asymmetric particle and/or fiber board. We made a serie of asymmetrical boards, with a different proportions and sizes of particles in each layer. We determined the bending strength, the modulus of elasticity, tensile strength, water absorption, density and thickness. The best properties were determined for two-layer particleboard, consisting of 50 % big particles and 50 % medium - sized particles. The absorption of water was higher in board, with a higher share of fibers and fine particles on the surface. The results showed that density of board is increasing with increasing share of fine particles. The bending strength of the asymmetric board is higher, when the larger particles are on the underside of the load. The bending strength of the asymmetrical board was approximately 33% lower than the bending strength of the symmetrical board.
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