Abstract: In an attempt to quantify the impact of waterlogging on urban road network traffic operation, the neighborhood topological potential of the waterlogged urban traffic road network was researched. First, the dual topological diagram of the urban road network was constructed with road sections mapped as points and intersections as edges. Subsequently, according to the principle of the potential function, parameters including the shortest topological distance between nodes, the relief height difference transfer weight, the throughput at dual nodes of road network, and the influence of potential field were determined. On this basis, a neighborhood topological model of the impact of waterlogging on urban traffi network was established, and the model was solved by using the golden section optimization algorithm. The model was applied to analyze the evolution of topological potential of urban road network under different depths of waterlogging in the flood-prone area in Xiling District of Yichang City as a case study. Results demonstrate that when the depth of waterlogging reaches 15 cm or more, the topological potential of each road section decreases by over 20%. With the increase of waterlogging depth at peak and flat times, the topological potential of nodes fluctuates gently before sharp decline. The topological potential value reaches the maximum between Xiling 1^st Road in waterlogging section and the road section in the first-level domain; but reduces between other road sections as distance increases. The study reveals the law of the influence of waterlogging on the neighborhood topology of urban traffic road networks, and is expected to provide a theoretical basis for urban waterlogging management and traffic control.

Key words: waterlogging, urban road network, topological potential, evolution characteristics, golden section algorithm