Multiscale analysis of urban transportation network resilience to earthquake-induced disruption in densely built environments of Istanbul

Urban road networks are critical for maintaining accessibility and emergency response after earthquakes, particularly in densely built areas. This study examines how the spatial pattern of earthquake-induced road blockages affects the structural resilience of a road network in Istanbul. The intact network was compared with two hypothetical scenarios in which the same number of links was blocked, either in a dispersed or localized pattern. Connectivity, intersection density, and changes in network shape across spatial scales were evaluated together. Results show that the spatial arrangement of blocked roads strongly influences network response. Dispersed disruption caused a much larger loss of high-density intersection areas, whereas localized disruption produced a greater reduction in network redundancy while preserving much of the original dense structure. Both scenarios also simplified the spatial organization of the surviving network. Combining these complementary indicators provides a basis for identifying vulnerable road networks and supporting post-earthquake transport planning.