In structural engineering, seismic assessment of existing structures is a crucial issue to provide adapted decisions in a vulnerability reduction context. Amongst the widely range of technical solutions for structural upgrading, external reinforcement by Fiber Reinforced Polymer (FRP) is an interesting tool. Nevertheless, the use of FRP as a retrofitting method is limited, one of the reasons being the lack of predictive numerical tools allowing the vulnerability assessment. Based on a case-study, this paper presents a simplified modeling strategy to assess the seismic vulnerability of an existing reinforced concrete building before and after FRP retrofitting. More specifically, the structure is simulated using multifiber beam elements, the model is validated with in-situ ambient vibrations records and a simplified method to consider FRP retrofitting is proposed. Non linear dynamic analysis studies are performed using a synthetic earthquake signal according to the Eurocode 8. Finally, local indicators, based on the European Macroseismic Scale (EMS 98), are adopted to quantify the damage level in the structure, before and after its FRP retrofitting.Keywords: earthquake; vulnerability; retrofitting; FRP; concrete; multifiber beam
