Experimental study and spring-component modelling of extended end-plate joints in fire

In order to investigate the fire-resistant capacity of extended end-plate joints, an experimental study was performed by using a furnace on four full-scale specimens made with H-shaped steel. The failure characteristics and failure modes of the extended end-plate joint specimens in fire were obtained from the experiment. The influence of rib stiffeners and depth of end-plates on fire-resistant capacity of the joints was found by comparing the capacity of the joints with and without rib stiffeners and different depths of end-plate. In addition, this paper also describes a spring-component model employed for predicting the behaviour of extended endplate bare-steel joints at elevated temperature. The components of a joint are considered to consist of spring components with predefined mechanical properties, i.e. stiffness and strength. The response of the joints subjected to elevated temperature can be predicted by assembling components, the stiffness and strength of which are assumed to degrade with increasing temperatures based on the recommendations presented in the Chinese Technical Code on Fire Safety of Steel Building Structure. It is demonstrated that the results from the model agree with experimental data quite well.