Quantification of model uncertainties for reinforced concrete columns subjected to fire

In structural fire engineering, several methods co-exist for the determination of the fire resistance of reinforced concrete compression members. However, there is no general agreement about which method should be preferred, and no comparative analysis of the accuracy of the methods is available. One approach to judge on the accuracy of a given method is to apply it for recalculation of well-defined laboratory test and to evaluate the difference between experiments and simulations. The aim of the article is to present a methodology to obtain, from the results of recalculation, relevant statistical key data for the probabilistic characterization of the model uncertainties. Methods of descriptive statistics are applied for the evaluation of the results of the recalculation of laboratory test. In case of prior knowledge from previously published results, methods of inferential statistics are also examined to adjust the statistical key data. In this case, the use of a response surface methodology with descriptive statistics is further presented in order to cross check the results of the inferential method. The application of the presented framework is demonstrated for reinforced concrete columns subjected to a standard fire, but is also applicable for any resistance model in civil engineering.