Steel Buildings in Europe

Part 7: Fire Engineering 7 - 1 1 INTRODUCTION Due to the particularities of single-storey buildings, the life safety objective in case of fire can be met easily without onerous fire resistance requirement for the structure. However, other safety objectives have to be taken into account if the collapse of these buildings or a part of them may be accepted. In consequence, many European fire safety building regulations are moving toward acceptance of alternative fire safety engineering designs. Prescriptive rules can then be replaced with performance based requirements, such as adequate fire behaviour of the structure, aimed at satisfying fire safety objectives that include life safety of people (occupants and fire-fighters), protection of environment, property protection and business continuity. Benefits and successful application of the performance-based approach to building fire safety designs have already been well demonstrated for single- storey buildings, especially where fire resistance was required, allowing in some cases more innovative, cost effective and safer solutions to be adopted. To help the structural fire design of buildings, a new set of European Standards has been developed, the Eurocodes. The Parts of the Eurocodes that are relevant to the fire design of single-storey building consist of EN 1991-1-2 [1] (which includes principal concepts and rules necessary for describing thermal and mechanical actions on structures exposed to fire) and Parts of material – specific Eurocodes dealing with the fire design of structures, such as EN 1993-1-2 ,[2] , related to steel structures and EN 1994-1-2 [3] related to composite steel and concrete structures. The fire parts of Eurocodes provide at present a wide range of calculation methods. They allow engineers to follow either a prescriptive approach to meet the fire safety requirements, as specified in national building regulations, or to carry out on the basis of performance-based rules, a fire safety engineering design that involves in general more complex computational analysis and provides more accurate answers to fire safety objectives. The present guide provides an overview of the current design methods available for evaluating the fire performance of single-storey buildings composed of either steel or composite structure as well as their application fields. Simple calculations methods, easy to use, and more advanced calculations models are dealt with separately. Moreover, to allow quick assessment, simple design rules are given to assess quickly whether the structural behaviour of steel structures of storage and industrial buildings fulfils the fire safety objectives required by the fire safety regulations for industrial buildings. This guide aims also to help the engineer to understand more clearly the different calculation methodologies and to carry out the structural fire design of single-storey building according to the Eurocodes, from a relatively simple analysis of single members under standard fire conditions to a more complex analysis under real fire conditions.