In the thesis, the influence of salt (sea) water on the tensile shear strength and quality of adhesive joints of two-layer glued laminated timber made of Robinia pseudoacacia and Tectona grandis lamellae glued with a one-component polyurethane (MITOPUR E45) and a two-component epoxy (West system A pack 105/206) was investigated. The 600 mm x 135 mm x 4.7 mm lamellae had a moisture content of 9% (teak) and 12% (robinia). The epoxy adhesive mixture was prepared in a 5:1 ratio (resin : hardener). The gluing was carried out at room temperature of 23 °C and 65% RH, at a specific pressure of 12 bar in a hydraulic press. The PUR adhesives were cold-pressed for 60 minutes and the EP adhesives for 360 minutes. The bonded assemblies were sawn into shear test specimens and divided into three groups according to the standard SIST EN 204:2016, so that the shear test for the first group of specimens was carried out after seven days of conditioning in a climate of 20 °C/65%, the second group after seven days of conditioning at 20 °C/65% RH and four days of soaking in saltwater, and the third group after seven days of conditioning at 20 °C/65% RH, four days of soaking in saltwater and another seven days of conditioning at 20 °C/65% RH. A ZWICK Z005 universal testing machine with tensile shear test jaws was used to test the test specimens. The best results were recorded in the first group where the specimens were not exposed to saltwater. The worst results were observed in the second group, where the specimens were tested wet. For both wood species, PUR adhesive gave better results than EP adhesive. Among the studied combinations, the PUR adhesive-bonded teak adhesives showed the best resistance to saltwater exposure.
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