Behaviour of steel reinforced concrete (SRC) joints with restrained SRC beams exposed to full-range fire

Steel reinforced concrete (SRC), as a typical type of steel-concrete composite structures, is increasingly adopted in high rise buildings due to its excellent structural performance. A few studies have been done to investigate the fire performance of SRC columns in the past, but limited work has been done to study the fire performance of composite joints with SRC components. Han et al. experimentally and theoretically studied the behaviour of SRC column to SRC beam cruciform joints subjected to ISO-834 standard heating fire, which provided valuable exploration to understand the response of this type of composite joint in fire. For a real structure subjected to a fire and surviving from the fire, the structure experiences the ambient loading, heating with external loads, cooling with external loads and post-fire phases. Previous research has demonstrated the significant influence of initial loads and cooling on the fire performance and post-fire performance of structures, but no such research work has been extended to SRC joints. Against the above background, in this paper, a numerical model is developed to simulate the SRC column to axially and rotationally restrained SRC beam joint, which is isolated from a planar frame. A full-range analysis is performed to understand the response of this type of composite joints under the entire load and fire phase.