Benchmarking the seismic design of bridges based on the new generation of Eurocode 8: A case-study example from Slovenia

In seismically active regions such as Slovenia, Eurocode 8 plays a pivotal role in the design of earthquake- resistant structures. Currently, the Eurocode standards are undergoing significant revisions, with the second generation of standards expected to be released in 2028. This paper focuses on emerging implications of the provisions in the draft of the new Eurocode 8 related to the seismic design of bridge piers, using a case study of a bridge over the Sava River in Ljubljana, Slovenia. For the purposes of the study, the bridge is redesigned employing both the conventional force-based approach and the newly introduced displacement-based approach. The differences in the required amount of reinforcement and the achieved seismic performance of the bridge resulting from the two approaches are evaluated and discussed. Results indicate that the design according to displacement-based approach yields approximately 25 % less longitudinal reinforcement in bridge piers.