Beams with corrugated web at elevated temperature, analytical and numerical models for heat transfer

In the case of corrugated web beams, based on experimental results, it was noticed that temperature development along the height of the web has a distinct pattern compared to the flat web beams. The particularity consists of a temperature decrease in the web, in the vicinity of the flange-to-web junction, assigned to the heat transfer by conduction and radiation. On this assumption, starting from the simple relations given in the fire design codes an analytical model is developed considering the heat conduction from the web to the flanges and the radiation heat transfer between web and flanges. The paper presents the results of the proposed analytical method against the experimental results and the numerical simulation. Both analytical and numerical models are compared to the experimental results obtained from the isolated element fire test and the real building fire test. A parametric study on the influence of the geometric dimensions is performed regarding also the time interval for the temperature development. For short term fire exposure, the web exhibits non-uniform temperature along the web height, while for long term fire exposure the entire cross-section tends to a homogeneous temperature.