BEHAVIOUR OF THE REVERSE CHANNEL CONNECTION BETWEEN AN I-BEAM AND CFT COLUMNS IN THE FULL-SCALE FIRE TESTS

This paper presents the results of the investigation on the coupled joint-structure behaviour of the composite sub-frame, using the reverse channel joints between an I-beam and the concrete filled tube (CFT) columns subject to ambient temperature and fire conditions. The experimental programme performed at Department of Civil Engineering of the University of Coimbra is part of the framework of the European RFCS COMPFIRE Project, which the aim is to provide an integrated approach of the performance-based fire engineering design of composite structures including the joint performance under natural fire conditions (heating and cooling phases). The objectives of these tests are to provide experimental information on the entire behaviour of the reverse channel joints, including bending, compression due to restrained thermal expansion of the beam, local yielding and buckling and catenary action.