Research and design of novel demountable steel‐concrete composite beams

Abstract

Demountable steel‐concrete composite system, comprising steel beams and precast concrete panels connected by demountable shear connectors, are developed to support sustainable construction by enabling reuse. Connector behaviour was characterised by push‐out tests, which verified adequate performance. The global response was assessed through beam tests, confirming that the developed system exhibited elastic‐plastic behaviour with adequate stiffness, resistance, and ductility, accompanied by significant plastic deformation and panel slip, while elastic behaviour was observed at serviceability load levels, without permanent deformation or damage, demonstrating potential for dismantling. Calibrated favourable and unfavourable connector mechanical models, derived from the push‐out tests, were combined to provide an enveloping and safe representation of the structural response for use in numerical simulations and calculations. A Eurocode‐based design algorithm is proposed to determine the effective connector resistance using a cosine‐based slip distribution refined by a weighting function, thereby enabling the prediction of plastic moment resistance. Besides, connector stiffness is provided for the elastic determination of moment resistance, deflection and end slip.