Experimental research on the determination of the main parameters affecting the behaviour of reinforced concrete columns under fire conditions

The design of reinforced concrete columns under fire conditions is generally made on the basis of national and international recommendations. The CEB/FIP recommendations have been used for many years. Recently, in the framework of the Eurocodes, the document ENV 1992-1-2 (Eurocode 2-1-2), Structural fire design, has been approved by Commission CEN/TC250/SC2 of the European Committee for Standardization. In the CEB/FIP documents and in Eurocode 2-1-2 the main part is devoted to design from tabulated data containing the dimensions of the cross-sections and values for the concrete cover. The use of simplified calculation methods is not current practice for concrete elements, while they are widely used in the case of steel. The determination of the temperature distribution in the cross-section does not facilitate the development of a simplified method. Furthermore, in columns there is a wide scatter of experimental results. In order to gain additional information, an extensive experimental research programme on the behaviour of reinforced concrete columns under fire conditions, financially supported by the Belgian Funds for Fundamental Collective Research (FRFC-FKFO), has been performed at the Universities of Liege and Ghent. In this article the results of this research are presented and the influence of the main parameters is analysed.