Abstract: Urban transportation capacity declines after disasters, and the distribution of original traffic flow is no longer applicable. To ensure normal economic and social activities, a traffic flow allocation method based on improved ant colony algorithm is proposed. Firstly, the influence factors of road network capacity are evaluated for the construction of road quality evaluation system. The road quality is used for improving the heuristic factor in an ant colony algorithm. Secondly, random nodes are added and the updating mechanism of pheromones are improved to expand the search range of ant colony. Finally, the improved algorithm is applied to allocate the total urban traffic in batches and obtain the traffic distribution maps. The results show that the improved algorithm comprehensively considers travel distance and road quality. It is more in line with the traffic flow distribution requirements than before, and the improved algorithm has a better path optimization. It provides suggestions and support for post-disaster relief work and traffic assignment decision of post-disaster road network.

Key words: traffic flow assignment, improved ant colony algorithm, road quality, road network, travel distance