Classes of cross-sections of steel structural elements in the fire situation

Abstract

In the paper the analysis of the influence of fire load on class of cross-section of steel structural elements is presented. In the fire situation some cross-sections may have a different class than at room temperature. Special attention is focused on steel structural elements which are Class 3 at room temperature and Class 4 in the fire situation. The examples illustrate a steel element, which obtain different class of cross-section at room temperature and in the fire situation. The reduction of critical temperature and fire resistance time is also taken in to account. The structure under consideration pertains the steel beam, which is a part of the existing building in Poznan. In the paper, the comparison between fire resistance of the beam using simulation of fire in FDS software and procedure according to standard time-temperature ISO curve is presented.