ASSESSMENT OF TRAM-INDUCED VIBRATIONS ON EARTHQUAKE-DAMAGED BUILDINGS

The interaction between urban tramway infrastructure and earthquake-damaged buildings presents a significant challenge for structural engineers and urban planners, particularly in densely populated, heritage-rich city centers. This paper examines the impact of vibrations induced by tram traffic on the structural integrity of earthquake-damaged buildings, through a case study of a historical masonry structure damaged in 2020 Zagreb earthquake. Utilizing vibro-acoustical analysis and data processing in DIAdem, the study derived transfer functions from measured tram and building vibrations to define the correlation between tramway vibrations and building responses. Results indicate that certain operational scenarios, such as track irregularities and higher tram speeds notably increase vibrational amplitudes, potentially leading to progressive structural damage over time. This analysis highlighted the cumulative effects of low-amplitude but repetitive vibrations on earthquake-damaged masonry, including the propagation of micro-cracks and loss of material ductility. The study emphasizes the importance of mitigating tramway-induced vibrations by incorporating these insights into structural maintenance and infrastructure planning, in order to protect damaged structures and enhance sustainable urban resilience in regions affected by earthquakes. Recommendations include implementation of advanced monitoring systems in order to promptly address and mitigate these risks, enabling targeted maintenance of tram tracks, particularly repairs of irregularities and optimization of vehicle speeds.