Abstract
Aim: The purpose of this paper is to present the principles of fire safety verification for concrete structures in accordance with Eurocodes (PNEN norms). Introduction of these codes into Polish design practice, for analysis of structures exposed to fire conditions, set a new dimension in the content and range of additional detailed requirements, which need to be satisfied during the building design stage.
Introduction: In compliance with Regulation (EU) No 305/2011 of the European Parliament and of the Council (previously – EC Directive 89/106), and provisions of PN-EN 1990, fire safety constitutes one of the basic requirements for structure design (apart from durability and reliability). Guidelines for the determination of specific fire interaction characteristics are included in PN-EN 1991-1-2. Parts 1-2 of individual structural Eurocodes (PN-EN 1992-1-2 for concrete structures) and reveal verification methods for fire resistance of structural elements. Whereas the determination of specific detailed fire resistance requirements (load bearing and/or separating functions – R, EI, REI), for structural elements of buildings, are based on national regulations.
Methodology: The article describes a range of potentially acceptable fire models (standard; natural – simplified or advanced) as well as provides information about principles for verification of structures for fire conditions. Additionally, the study characterized behaviour of concrete structures in fire conditions, indicating the basic material parameters for concrete and reinforced steel, which determine the behaviour of structural elements in such conditions and provide the basis for a structural analysis. The major area of research interest, involving the determination of concrete structures fire resistance, was achieved. The study imparted fire resistance verification methods for concrete structures, which included; fire tests,descriptive techniques, simplified and advanced calculation methods. Some selected methods from PN-EN 1992-1-2 are described in detail. Additionally, key information was presented, which dealt with analysis and classification of fire damage to concrete structures. Both are essential elements for an assessment of the technical condition of structures after a fire and conclusions concerning the level of safety for such structures.
Results: The study highlighted most significant information concerning obligatory Eurocodes procedures relating to the design of concrete structures, which may be exposed to the influence of fire. This encapsulated a thermal and mechanical analysis for assumed fire scenarios and techniques with a potential for application in the verification of fire resistance of structural elements.
Keywords: fire safety, concrete structures
Type of article: review article