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In lack of seismic provisions in the pre-Eurocode ages, most of the existing Hungarian bridges are not designed for seismic actions. It is questioned whether they are able to retain their structural integrity after a considerable seismic event or may suffer significant damages. Based on the evaluation of a governmental bridge database, ten typical bridge types could be distinguished, covering 85% of the total amount of about 3200 bridges of higher level roads. In present study only prestressed multi-girder bridges are investigated. First, multi modal response spectrum analysis is used for parametric studies to determine critical components and layouts. Nonlinear response history along with multiple stripes analysis are also carried out for bridges sampled by Latin Hypercube method. Fragility curves of each critical component, furthermore the reliability of the selected critical bridges are determined. The analyses show that brittle shear failure of piers may occur in the case of longer bridges, the relatively high flexural ductility of the members cannot be utilized. Using fibre reinforced polymers can be a possible retrofit method, however higher reliability can be achieved in exchange of increased costs applying concrete overlay or steel jacket.