Seismic upgrading of existing RC buildings by slender steel shear panels: a full-scale experimental investigation

In the present paper the seismic upgrading of an existing RC structure by using slender steel shear panels is examined. Based on a preliminarily experimental evaluation of the performance of the bare RC structure, an ad hoc design procedure has been developed in the framework of the performance based design methodology. The applied device, whose configuration has been defined also according to both simplified and refined numerical analyses, is able to significantly enhance both the strength and the stiffness of the primary structure. It has been installed within a reaction steel frame, positioned into the bare RC structure, which is composed by members designed in order to remain in elastic regimen under the tension field action developed by plates. Since the original RC module was not able to withstand significant values of horizontal forces, the reinforcing of both the first level beam and the foundation beam by means of coupled channel steel profiles and threaded bars has been done. Finally, in order to assess the reliability of the proposed intervention, a full scale cyclic experimental test has been performed on the upgraded structure, confirming the effectiveness of the adopted technique as well as the validity of the proposed design procedure.