Analysis of transportation network vulnerability under flooding disasters

The transportation network plays an important role in people's daily activities. At the same time, serious flooding disasters frequently damage the transportation infrastructure and network around the world. The vulnerability of the transportation network has attracted much attention. Understanding transportation network vulnerability can enhance prevention and response capabilities during disaster events and emergency incidents. However, current methods for evaluating transportation network vulnerability still have many disadvantages. This research provides an introduction to analysis of transportation network vulnerability, followed by a review of research addressing transportation network vulnerability. A new accessibility-based methodology addressing travel modes was developed to evaluate transportation network vulnerability under flooding impacts. A case study based on data from Hillsborough County, Florida, was conducted to verify the established model. ArcGIS was utilized to identify the inundated segments. Different flooding scenarios were applied in CUBE to update the shortest travel time changes under flooding. Networkwide accessibility and vulnerability values under each scenario were then calculated. Finally, accessibility values calculated with the proposed accessibility-based method and the Hansen accessibility index method were compared. Comparison of results shows that the results of the two methods are quite close, but the proposed method yields normalized values, which make the results clearer and provide more levels of accessibility loss. Research results of the study can support decision making for urban transportation under flooding disasters resulting from extreme weather events and sea level rise.