External steel exoskeleton for a life-cycle upgrading approach for seismic retrofit of existing RC framed structures

In many regions of the world with medium or high seismic hazard the majority of existing buildings does not comply with prescriptions of current seismic codes or were even designed considering gravity loads only. Hence, existing RC buildings are often seismically deficient. In addition, they may present excessive energy consumption. In this framework, this study investigates a new retrofit technique for buildings with RC framed structure. The intervention requires the addition to the building of a vertical external steel exoskeleton. This research aims at sounding the impact of the proposed retrofit solution by nonlinear dynamic analysis in terms of lateral strength and story drift ratio, in order to quantify the expected impact of the proposed retrofit intervention.