Behaviour of Perfobond shear connectors at high temperatures

In composite steel and concrete construction, the most extensively used and known shear connector is the Nelson or stud connector, automatically welded to the beam flange. Some alternative connectors account for the contribution of the mechanical interlock of the concrete in holes or other indentations drilled in steel plates welded to the beam flange. This is the case of the Perfobond and Crestebond shear connectors recently studied by several authors. However, there is a lack of studies of their performance in fire.In this paper, we describe a research study on the behaviour of the Perfobond shear connectors under fire conditions. The specimens were first heated from room temperature up to a target temperature and then they were loaded up to failure as a way to assess the connector’s shear resistance and its ductility at high temperatures.The main purpose of this research was to investigate the influence of the number of holes in the Perfobond shear connectors, the presence of transversal reinforcement bars passing through these holes, and the behaviour of two connectors placed side by side at high temperatures. We also compared the behaviour of these connectors at room temperature and at high temperature.The results of this research showed mainly that the load capacity at high temperatures of these connectors was not as good as at room temperature.

► We report a study of the behaviour of Perfobond shear connectors under fire conditions.
► We present an assessment of the connector’s shear resistance and its ductility at high temperatures.
► We consider the influence of several parameters on the connector’s shear resistance.
► High temperatures significantly affect the Perfobond connector’s shear resistance.