Research on Fire Resistance of Steel Floor Beams During Reconstruction of the UN Office Building in Ukraine

Abstract Due to ongoing military operations in the territories of our country, a critical issue has emerged regarding the protection of public buildings from damage caused by missiles, drones, and artillery shells. Safeguarding these buildings from such destructive forces is an extremely challenging task, and in many cases, it may seem nearly impossible. Nevertheless, while complete protection against these types of attacks may not be feasible, there are still methods available to mitigate the consequences of such impacts. One effective approach is reinforcing the load-bearing structures of the building to withstand the intense heat generated by fires caused by these attacks. Research has shown that during a fire in buildings with steel structures, the load-bearing elements begin to deform significantly and lose their structural integrity within just 15 minutes. This rapid degradation makes steel structures much more vulnerable compared to reinforced concrete, which provides greater resistance to fire. The collapse of steel load-bearing structures occurs at a much faster rate than that of concrete ones, leading to severe material damage, increased structural risks, and, most importantly, heightened danger to the lives of individuals inside the building. Therefore, enhancing the fire resistance of these structures is critical for minimizing potential harm.