Influence of partially-restrained connections on the overall seismic behavior of steel-concrete composite frames: a mechanical modeling approach

The paper deals with a parametric study of the behavior of partially-restrained (PR) steel-concrete composite earthquake-resisting frames. The frames have been designed according to Eurocode provisions, using a simplified procedure. The response of the semi-rigid connections during the seismic event and its influence on the global structural behavior are investigated. The beam-to-column connections have been modeled by means of a mechanical approach. This particular technique allows to describe with unprecedented detail the actual behavior of the separate components of the connections during the load history. It is possible to clearly point out the reciprocal influence between the structure as a whole and the connections. The paper presents the main capabilities of the modeling technique adopted, together with the description of the response characteristics of the designed frames.