Fire resistance of concrete-filled steel tube beam-column under elevated temperatures and cyclic loading

This article aims to provide an overview of the fire resistance of concrete-filled steel tube beam columns and the importance of fire resistance in building design and construction. Ten experimental models were developed to predict the behavior of different types of concrete-filled steel tubes and beams-columns under Fire resistance conditions (ISO-834) under cyclic loading in two groups. The results show the type of concrete effect on moment-rotation characteristics. Also, increasing the length of the stiffener on the column increases the load and moment capacity, but also affects the failure mode. Moreover, the ideal situation is to use PP fiber concrete in concrete-filled steel tube structural elements where displacement and rotation capacity are prominent. Withal, the recycling of fire-exposed steel beam-to-column tube element is available by filling the inner space with C50 and/or polypropylene fiber reinforced concrete, also as a fireproof member.