Acceptable range for structural fire resistance in performance based design

Structural fire safety engineering is increasingly moving away from prescriptive design rules to what is generally referred to as Performance Based Design (PBD) in which the structure or structural components are designed to satisfy performance requirements. By taking into account the specific characteristics of the structure, a PBD can allow for more directed investments in safety, resulting in structures which are both more economical and safer compared to designs according to traditional prescriptive rules. Although stakeholders mostly agree that the structure should have a good fire performance, determining the specific performance requirements can prove difficult, especially when the opinions of stakeholders with respect to key design parameters diverge. In this paper a decision support tool for investments in Life Safety is introduced and applied to determine an Acceptable Range for the structural fire resistance time for concrete slabs. The support tool takes into account the uncertainty related to amongst other the fire load density and the mechanical properties of the structural element, and can be used as a tool for aligning potentially diverging positions of different stakeholders