08.08: Prefabricated demountable concrete and FRP decks in composite structures

Abstract

ABSTRACTWelded shear studs are traditionally used to achieve composite actions between steel beams and concrete slabs. Relevance of composite structures for future applications in construction sector is increased by using demountable shear connectors which enables easy reuse of structures. The latest achievements of using demountable bolts embedded in prefabricated concrete slabs as shear connectors are presented in this paper. The focus of the investigation is on possible influence of execution tolerances on the level of composite action. The second issue addressed in the paper is use of Fibre Reinforced Polymer (FRP) composite deck instead of concrete slabs. FRP decks have high strength‐to‐weight ratio which reduce the total weight of the deck. Use of decks which have smaller self‐weight facilitates the transport and execution process and reduces foundation costs especially in high‐rise buildings. FRP composites are used in aerospace, automotive and shipbuilding industries for decades. They are considered as a maintenance free material. The main obstacle for wider applications of FRP material in construction is relatively a low stiffness of composites made of glass fibres and thermoset resins. Use of sandwich systems and hybrid decks, which combine FRP and the steel to increase the stiffness, are investigated in order to satisfy the design requirements. The third item of modern composite structures considered in this paper is use of high strength steel (HSS) grades to optimize the weight/strength ratio of structures. Results of a short parametric study using welded hybrid beams, combination of HSS and mild steel grades, is presented. This indicates significant reduction of weight and costs compared to the design using rolled cross section beams.