Performance-based fire design of complex structures

The problem of structural fire safety in the recent years has gained a predominant position within the engineering design, with the affirmation of performance-based structural codes and standards, replacing more and more the traditional prescriptive ones. This is because nowadays, structures always bigger and more complex are designed and built. In modelling such complex structures, there are important aspects and relevant uncertainties that need to be taken into account. This paper focuses on the application of the performance-based fire design to this kind of structures; the systemic approach is identified as the proper tool to manage all the aspect related with the problem. A general framework is presented for this purpose and it is applied to a facility made of steel for the storage of helicopters, with a relatively complex geometry subject to fire. The structure is of interest since, due to its occupancy, it is prone to elevate fire risk. The modelling of the problem proposes the use of non-linear analysis that includes thermo-plastic material, geometric non-linearity and the representation of fire action are done according to a standard parametric curve.