Plywood is a wood-based material that, due to its good properties, has found applications in many areas of the wood industry, transport, and construction. Plywood is fabricated from multiple layers of veneer glued together with the grain direction of each layer of veneer perpendicular to that of the adjacent layers. In order to improve primarily mechanical properties, plywood is reinforced with various fibers, both natural and synthetic. Basalt is used in various forms as a material for reinforcing composite materials. Basalt mesh is primarily used in construction to improve the properties of wall and road structures. In order to determine the possibility of using basalt mesh in the production of wood-based composite materials, plywood reinforced with basalt mesh was produced in laboratory conditions. One, or two, or three basalt meshes were placed in different positions in the panel construction. The manufactured plywood reinforced with basal mesh was tested in accordance with EN 310. The paper presents the results of the bending strength test depending on the quantity and position of the basal mesh in the plywood construction.

The favorable characteristics of veneer boards—plywood—enable their wide application. There is also the possibility of enhancing plywood, such as by coating it with various films, applying coatings, reinforcing it with fibers from different materials, and using improved adhesive formulas. Basalt fibers, as a natural and environmentally friendly material, are used in various forms with quite good characteristics. Results from various tests conducted in recent years indicate an improvement in the mechanical properties of composite boards, including plywood reinforced with fibers like basalt fibers. These tests were focused on determining the position and contribution of basalt fibers in the board’s structure, as well as the application of certain environmentally friendly adhesives. For this study, samples of composite material based on wood, specifically plywood reinforced with a basalt mesh, were prepared. The basalt mesh was placed within the plywood structure in various combinations of position and amount. Subsequently, a three-point bending strength test was conducted to determine the impact of the basalt mesh on the strength of the plywood. The increase in strength opens up possibilities for expanded use, material savings, and a reduction in the overall weight of the structure, which is crucial in certain applications of such boards.

In the process of creating composites, especially if we talk about wood-based composites, great attention should be paid on a variety of factors which affect the final composite properties.One of the essential elements is proper adhesive selection. Most common used are synthetic formaldehyde adhesives. We are aware how dangerous emission of free formaldehyde can be; we tend to minimize its usage. Using adhesives which are safe for the environment and humans as well, we tend to find safer composites which are ecologically acceptable and recognized as a better option.The paper briefly describes the adhesives used so far and their dangers, and selects several types of adhesives with basic characteristics that can meet the requirements for the production of ecologically acceptable composite panels, with an emphasis on wood-based composites. Certain tests and achievements in the development of these adhesives are also presented.

Determination of tensile shear strength of lap joints is carried out according to three standards: BAS EN 205:2018 for adhesives used for non–load–bearing structures, and according to BAS EN 302-1:2014 for adhesives used for the manufacture of load-bearing structures and according to EN 14257:2019 for lap joints who are exposed to elevated temperatures. The paper presents the results of tensile shear strength of lap joints made of solid fir/spruce (Abies alba ssp./Picea abies spp). Tensile shear strength was tested in 4 groups of tests samples. The Group 1 consisted the samples were 7 days in standard atmosphere [20/65]. The Group 2 consisted the samples were previously soaked in water at (20 ± 5) °C, then recondition in standard atmosphere [20/65]. The Group 3 consisted the samples were previously 6 h soaked in boiling water 2 h, then soaked in water at (20 ± 5) °C; the samples tested in the wet state. The Group 4 consisted the samples were previously exposed to heat in a preheated fan oven, at (80 ± 2) °C, for (60 ± 2) min. The test results can be applied for gluing windows, doors, stairs, high-frequency gluing, veneering panels, etc.

Particleboards are used in the manufacture of furniture, as well as the furnishing of structures and prefabricated homes. Their quality dictates where they can be used and how long they can last. The boards’ characteristics deteriorate as they are used. To examine the change-degradation of the properties of the boards are exposed to the effects of the external climate (rain, snow, wind, sun) or regimes of accelerated aging. For this purpose, a degradation test of the properties of wood-based panels was performed, which aims to create a model that will describe the change in bending strength of the mentioned panels. The paper presents the results of bending strength and thickness swelling tests of 16 mm thick particleboards that were exposed to accelerated aging regimes, and the basic model of property degradation.

SAŽETAK: Uporaba drvenih lameliranih nosača posljednjih desetljeća sve je veća zahvaljujući upravo karakterističnim prednostima ovih nosača u odnosu na nosače od drugih materijala – mala vlastita težina (od 400 do 600 kg/m3), dobra mehanička svojstva u odnosu na težinu (tlačna čvrstoća od 40 do 80 MPa, vlačna čvrstoća i do 180 MPa), mogućnost proizvodnje izrazito dugih nosača (dužine i do 100 m), te mogućnost različitog oblikovanja (nosači mogu biti ravni, zaobljeni, kružni). Proces proizvodnje drvenih lameliranih nosača razlikuje se u zavisnosti od primijenjenog tipa tehnologije – klasična ili sofisticirana (automatizirana) tehnologija. Linije za proizvodnju drvenih lameliranih nosača primjenom klasične i sofisticirane tehnologije prikazane su u ovom radu. Također su predstavljeni aspekti zaštite na radu pri izradi drvenih lameliranih nosača primjenom spomenutih tehnologija s težištem na zaštitu zdravlja i sigurnost na radu pri proizvodnji drvenih lameliranih nosača u Bosni i Hercegovini. Analiziran je proces proizvodnje drvenih lameliranih nosača i za svaku navedenu tehnologiju detektirana su moguća mjesta rizika i tip opasnosti za zdravlje i sigurnost na radu za radnike koji sudjeluju u procesu. U ovome radu prikazani su važni i potrebni koraci te specifične mjere zbog osiguranja zaštite zdravlja i sigurnosti na radu u procesu proizvodnje drvenih lameliranih nosača. Njihova primjena utječe na smanjenje troškova proizvodnje, pravnih sporova i stope bolovanja.