Methodology of fire safety analysis of metal structures

The paper presents a unified theory of metal structures at elevated temperature. The theory deals with time effects, which means that the influence of velocity of heating metal structures on the decrease of their load bearing resistance is considered. Defining time effects is indispensable when the analysis of structures with different temperature-time curves of fire is recommended. Such requirements were formulated in Standard Eurocode 1. Due to the lack of implemented methodology of analysis of load bearing resistance, they are not respected while analysing metal structures in fire. Such analyses must be connected with justification of the choice of a temperature-time curve (describing a more or less intensive fire) and calculations carried out consistently according to a theory of load bearing capacity which enables to consider the influence of heating velocity on the structure behaviour