Circular perforated steel yielding demountable shear connector for sustainable precast composite floors

A circular steel-yielding demountable shear connector is proposed. The connector consists of a short perforated circular hollow section (CHS) welded on a base plate which in turn is bolted on the top flange of a steel section. The connector provides longitudinal shear resistance in all directions through yielding of steel and is used in conjunction with precast hollow core slab units. The mechanical behaviour is first studied using a previously validated detailed finite element model simulating horizontal pushout tests, by conducting a series of parametric studies to identify all failure modes of the novel connector. Based on the results of the numerical pushout tests, design equations to predict the strength of the connector are proposed. A composite beam using hollow core slabs and various degrees of shear connection is then simulated to verify the applicability of the circular connector and the implications in the design of composite beams.