Authors: Nadia Baldassino, Martina Bernardi, Riccardo Zandonini
Editor: University of Trento – Department of Civil, Environmental and Mechanical Engineering - Trento (Italy)
Year of publication: 2017
DOI: 10.15168/11572_219182
All rights reserved: Nadia Baldassino, Martina Bernardi, Riccardo Zandonini

ABSTRACT

The importance of local ductility and the central role of connections to ensure a robust performance of steel-concrete composite structures subjected to accidental actions are nowadays well recognized. In addition, the dynamic nature of the phenomena associated to the accidental loads acting on structures has been found out. With reference to the steel and steel-concrete frames, the joints response is well approximated by the “component method”, codified also by the Eurocode 3 part 1-8. The components that influence most the rotation capacity and the ductility of the bolted beam-to-column joints are the column flange and the end-plate. These components are well modelled by the introduction of the equivalent “T-stub” elements. The response of the T-stubs subjected to quasi-static or cyclic tensile loads has been widely investigated over the years. On the contrary, the studies concerning their performance when subjected to tensile loads with higher loading rates are, at present, quite limited. For these reasons, in the framework of the “RobustImpact” project, in which the University of Trento was involved, a study on the influence of the loading rate on the T-stubs response was carried out. Twenty tensile tests on end-plate and column flange unstiffened T-stubs with different displacement rates were experimentally performed, besides complementary tests on bolts and structural steel. In addition, the corresponding numerical models were developed and calibrated. This document presents the experimental and numerical analyses and their main outcomes.