[en] concrete ; columns ; fire resistance ; fire tests ; calculation method ; spalling ; circular section
[en] The introduction sets the scene of the present paper i.e. the extensive research works performed at the University of Liege in order to derive acceptable calculation methods for the re design of concrete columns. It is explained that all previous works have been based on square or rectangular cross sections, for which corner spalling was observed very often, whereas circular section are nowadays becoming more and more popular. In order to examine the influence of the circular shape on the behavior under re conditions, an experimental research study has been performed recently at the University of Liege. This paper describes the test procedure, the observations made, and the values obtained for the re resistance. Theoretical methods have been developed for a quick, safe, and efficient design of concrete columns under re conditions. These methods have been applied successfully to the recently tested circular columns.