Assessment of Bearing Capacity of Steel Beam Under High-Temperature Effect

The article describes in detail the algorithm ofsteel beam analysis for high-temperature effects.The article's author describe the solution of thenonstationary thermal conductivity problem usingthe LIRA-SAPR software. After obtaining the resultsof the thermal conductivity analysis, the author usethem to assess the stress-strain state of a loadedsteel beam. This approach provides an in-depthunderstanding of how thermal loads affect the stressstrainstate of a steel beam and its ability to withstandloads in a fire.The study presented in this article considersthe nonlinear change in the thermal and physicalcharacteristics of steel and fireproofing material,which allows for a more accurate analysis of thetemperature distribution across the cross-section of asteel beam.In contrast to the simplified method of steel structuresfire resistance analysis, the method presented in thisarticle allows to obtain the temperature value at anypoint of the steel beam section at any time.After thermal conductivity analysis anddetermination of the temperature distribution acrossthe cross-section of the beam, the author proceedto the assessment of the stress-strain state of thestructure. The methodology for assessing the stressstrainstate presented in the article is to reduce themodulus of elasticity of the section and the ultimateresistance of steel. The author also compare theresults of the study with the results of a full-scaleexperiment.The article will be useful for civil engineers workingwith steel structures and researchers interested inthe impact of fire protection materials on the fireresistance of a structure. It provides valuable scientificand practical information that can be used to improvethe safety and reliability of steel structures in fireresistantenvironments.