Target safety levels for insulated steel beams exposed to fire, based on lifetime cost optimisation

The absence of clear target safety levels for structural fire safety severely hampers probabilistic structural fire design. In support of a generalized definition of target safety levels for structural fire safety engineering, optimum target safety levels for insulated steel beams are determined as a function of the fire characteristics by applying lifetime cost optimization (LCO) techniques. Where the fire development characteristics support the prospect of flashover, the Eurocode parametric fire curve is considered, otherwise fires are assumed to roam in search of fuel, leading to spatial variations in temperature, with thermal exposure to structural elements described via travelling fire methods. Fragility curves are derived as a function of, amongst others, the insulation thickness and fire load density, and applied in the LCO evaluations. The LCO results in an assessment of the optimum investment level as a function of the fire, damage and investment cost parameters characterizing the building. It is intended that the current contribution can be a stepping stone towards rational and validated reliability targets for PBD in structural fire safety engineering.

ISBN:9781315228914

Publication year:2019

BOF-keylabel:yes

IOF-keylabel:yes

Accessibility:Open