###### Abstract  
Tmber and timber products are renewable materials that, due to their durability and strength properties, meet the requirements of the construction industry, are widely used in buildings. An analysis of the scientific literature has shown that there is a lack of detailed research that fully investigates the influence of the rate of increase of the moisture content of the timber on the mechanical and, especially, the strength properties of the LVL panels. Upon immersion into water of the bottom of the specimen, the water starts rising quite quickly at the edge of the specimen, and the first six hours are the most critical. The levels of water rise inside the LVL specimen were less significant than at the edges. It was found that water significantly affects the bending strength of the panels, which, when the strength of the wet panel compared to the strength of the dry panel, decreases to 45% after one soak cycle and almost to 52% after two soak cycles. The tensile strength of the wet specimens is ~40% less than that of the dry specimens. The strength of the panels that were dried back to their initial state was found to be sufficient again, different from the initial strength only within the error limits; the strength properties of the building structure will not be affected. laminated veneer lumber (LVL); strength; water rise level; water absorption Article  
An Investigation of the Impact of Water on Certain of the Mechanical and Physical Properties of Laminated Veneer LVDL  
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M.; [PERSON]; [PERSON]. Constructions made using glued timber materials, such as laminated veneer lvl and cross laminated timber (CLT), can be used to reinforce concrete and steel structures and ensure better levels of protection against earthquakes [12]. In order to improve physical and mechanical properties, the LVL panels were reinforced with interwoven glass fibers [13; 14]. It was found that the density, impact bending, and shear strength of reinforced LVL were higher, while the tangential and volumetric swelling, moisture content, and specific impact bending were lower than those of LVL. Based on the results obtained during these studies, it can be stated that reinforced LVL can be used in load-bearing areas. The direction of the applied load was found to have an influence on the strength properties, both for timber and for LVL [15]. [PERSON] et al. have examined plywood using high-density polyethylene (HDPE), which was made by using supermarket plastic bags as a binder [16]. Increased density levels were found to exist alongside an increase in HDPE, which had a positive effect on the mechanical and physical properties of the LVL-HDPE composite board. The popularity and relevance of LVL panels is also evidenced by the number of studies carried out on the subject, which have examined and investigated various types of timber, along with the properties of combinations of different types of timber and their fiber orientations, the effect on the properties of LVL panels and the effect of various adhesives, binders, or finishing agents on the quality indicators of these building panels [17; 18; 19; 20; 21; 22; 23; 24]. During a study aimed to determine the effect of the span-to-depth ratio on the pendulum impact bending strength, it was found that the highest impact bending strength is at a span-to-depth ratio of twenty, and the lowest at a span-to-depth ratio of ten. Furthermore, the test results showed that the impact bending strength of all the specimens that underwent testing in the flatwise direction was significantly higher than that of the specimens that were tested in the edgewise direction [25]. The SPF was found to have a higher plane shear strength and modulus than the LVL [26]. The bending properties of common CLTs improved with the use of LVL in parallel layers, whereas they could be seen to decrease with the use of LVL in the cross-layer.