Fire Safety Science Digital Archive

An analytical model is presented to predict the response of restrained steel columns to elevating temperatures due to fire. A locally heated column was idealized as stub column in series with a spring representing restraint from the structure. The model incorporates thermal, creep and elasto-plastic effects which represents the most important material factors of the behavior of steel columns when exposed to fire. The significance of these effects at different stages of a fire is clearly identified. Axial deformation due to creep was found to dominate at high load levels, with thermal effects dominating at low load levels. The results obtained will be compared with future experimental testing.