THE IMPACT OF HIGH TEMPERATURES ON THE LOAD-BEARING CAPACITY OF WOODEN STRUCTURES

Problem statement. Wooden structures are widely used in construction both in Ukraine and globally. They offer numerous advantages over other building materials, which is particularly valued in the construction of residential and public buildings. However, wood is a combustible material, and in the presence of a high-temperature source, it can sustain burning. Recent scientific studies have increasingly focused on the destructive processes occurring in wood under the influence of high temperatures, particularly the burnout of surface layers of the structure to a critical level, which may lead to collapse. However, insufficient attention has been paid to other destructive changes that can reduce the integrity and load-bearing capacity of wood without visible signs of burning. The complexity and interdependence of different stages of the wood combustion process make it difficult, and sometimes impossible, to accurately assess its fire resistance and develop effective methods to improve the fire resistance of wooden structures. Currently, there are no practical and tested methods for assessing the fire resistance of such structures. Given this, there is a need for further theoretical research into the processes of heating and burning of wood during fires. To better understand the complex combustion process, it is advisable to divide it into characteristic stages, which can significantly influence the assessment of the structure's fire resistance. Purpose of the article to analyze the impact of high temperatures on the load-bearing capacity of wooden structures, particularly in fire conditions. The article examines destructive processes occurring in wood during heating, which lead to a reduction in its strength even without visible signs of burning. The article also emphasizes the need for further theoretical studies of heat and mass transfer processes to assess the fire resistance of wooden structures. Conclusion. Wooden structures have many advantages, but their fire resistance remains a challenge due to the combustibility of wood. A significant threat is posed not only by burning but also by destructive processes that can weaken the structures without visible signs of ignition. The complexity of the combustion process complicates the development of reliable fire resistance assessment methods, thus necessitating further research. The proposed mathematical models can help better understand the processes of heat and mass transfer and improve methods for assessing the fire resistance of wooden structures.