Civil Engineering Association

Analysis and modelling of the seismic behaviour of high ductility steel-concrete composite structures

In this thesis theoretical, experimental and numerical aspects and applications concerning the seismic behaviour of high ductility steel-concrete composite structure are analysed. The interest has been focused on the capability of framed structures to dissipate seismic energy by means of inelastic deformations. The basic design parameter in this approach is the ductility that should be considered as a conceptual framework in the Performance-Base Seismic Engineering (PBSE). PBSE has been developed encompassing the full range of seismic engineering issues to be referred to design of structures for predictable and controlled seismic performance within establishedlevels of risk.The attention has been focalised on different solutions of steel and steel-concrete composite beam-to-column joints assuring the necessary ductility that can be obtained not only through careful study of building morphology, structural schemes and construction details, but also through the rational use of materials. Three specific and related topics have been analyzed and detailed analyses and experimental tests on substructures have been performed in order to ensure large inelastic deformations and the necessary energy dissipation under earthquake strong motion. The results aiming at qualifying the dissipative and rotational capacities of a particular typology of beam-to-column joints are then illustrated and discussed. The objective of this study is to provide designers with precise rules regarding constructional solutions suitable to each scheme and to the associated design methodologies necessary for evaluating their performances.