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 build, with the use of particularly fire sensitive materials. In modelling such complex structures, there are important aspects that need to be taken into account, especially when setting the boundary conditions of the structural problem as defined by the design environment. This paper focuses on the application of the performance-based approach 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 elevated fire risk. The modelling of the problem proposes the use of nonlinear analysis that includes thermo-plastic material, geometric nonlinearity and the representation of fire action is done according to a standard parametric curve.