SEISMIC RETROFIT OF EXISTING BUILDINGS THROUGH THE DISSIPATIVE COLUMNS

A new replaceable hysteretic damper to better control seismic building damage, consisting of two or more adjacent steel vertical elements (columns) connected to each other with continuous mild/low strength steel shear links, is investigated in this study. New Dampers, called Dissipative Columns (DC), are continuously linked with X-shaped steel plates and provide additional stiffness and damping to a lateral system. The Dissipative Column has been conceived as a device installed within a frame or as an external damper to provide macro-dissipation. In fact, considering different configurations, a parametric analysis is developed, through non-linear pushover and cyclic analyses carried out in ABAQUS, in order both to evaluate the effect of the main geometrical and structural parameters and provide the design capacity curves of this new damper. Moreover, non linear dynamic analyses of an existing building without and with the Dissipative Columns have been performed in SAP2000 in order to evaluate the supplemental damping provided by the new damper. The DC can be considered a new damping device, easy to install in new as well as existing buildings in order to protect them from seismic damage.