Seismic Fragility Evaluation of Existing RC Frame and URM Buildings in Algeria

The main objective of this present work is to estimate the seismic fragility of typical existing buildings in the north part of Algeria, in which we evaluate the performance, the seismic vulnerability and the damage of reinforced concrete frame structures and URM masonry buildings, existing in dominant way in the city of Algiers (Algeria). An analytical procedure for the derivation of fragility curves is proposed. The capacity spectrum method and seismic damage potential for the city, starting from capacity and fragility curves, are then discussed. Different tools regarding the determination of capacity curves of different existing structural systems by using a non-linear structural analysis are implemented and explained. Four damage states are defined for both structural systems. The earthquake action is expressed in terms of spectral values and the seismic quality of the buildings; the probabilities of the damage states are obtained considering a lognormal probability distribution. An ADRS format has been used for the studied area where a significant damage is obtained for mid-rise and high-rise masonry buildings.