Developing seismic fragility curves for existing reinforced concrete structures in Algeria

This paper presents a method for developing fragility curves for assessing the seismic performance of existing reinforced concrete structures in Algeria. A two-storey 1980s reinforced concrete building in the northern city of Constantine was studied using the proposed method as part of a vulnerability assessment and strengthening proposal. Fragility curves for the existing and strengthened structure were derived and log-normal cumulative distribution function parameters were obtained for the four defined damage states by considering maximum inter-storey drift ratio. Incremental dynamic analysis was then used to assess spectral acceleration by conducting 300 non-linear time-history analyses based on 15 ground motions. The records were then selected and scaled to fit with Algerian design response spectra, and fragility curves were subsequently developed. The method can be used for any type of reinforced concrete structure in Algeria, including bridges.