Performance-based design of road tunnel fire safety: Proposal of new Swedish framework

Abstract

This paper contains a proposal of new Swedish framework for performance-based design of road tunnel fire safety derived from Swedish and European regulation. The overall purpose of the guideline is to protect life, health, property, environment, and key societal functions from fire. The guideline is structured into five key groups of requirements: #1 Proper management and organisation, #2 to limit the generation and spread of fire and smoke, #3 to provide means for safe self-evacuation, #4 to provide means and safety for the rescue service, and #5 to ensure load-bearing capacity of the construction. Each group contains a hybrid of prescriptive requirements, performance-based requirements, and acceptable solutions. Prescriptive requirements must be fulfilled, however, it is the choice of the design team to either adopt the proposed acceptable solutions, or to design alternative solutions by verifying that performance-based requirements are satisfied. For verification of performance-based requirements through risk analysis the operational, epistemic, and aleatory uncertainties are considerable. Therefore, a scenario-based risk analysis with several specified input variables and methods is recommended for verification of #3 and #5. Indispensable complements are scenario exercises, emergency exercises and similar methods that validate the design and highlight organisational aspects. The proposed design guide has been developed by the authors together with the advisory group established for the work.