Research on static and dynamic comprehensive evaluation of urban agglomeration road network integration based on catastrophe theory

The integration of urban agglomeration road networks is an inevitable trend of regional development. It is very important to build a scientific and reasonable evaluation system for the integration of urban agglomeration road networks. The existing research may not be sufficient to evaluate the road network level reliably if the city unit in the region is not considered enough. It is necessary to evaluate the level of road network integration from a dynamic perspective, in consideration of the economic scale of urban population and the level of road network in developing countries such as China is in the stage of rapid development. Therefore, this paper constructs an analytic hierarchy process (AHP)-catastrophe progression method evaluation model by considering the equilibrium degree and the fitness degree of urban unit road network. This evaluation model combines the integration of road network quantity, shape, and quality to evaluate the level of urban agglomeration road network integration from dynamic and static ways. Taking Beijing–Tianjin–Hebei urban agglomeration and Yangtze River Delta urban agglomeration as examples, this paper uses the road network data of urban agglomerations in 2010, 2015, and 2020 to make a comparative study. The results show that the growing trend of Yangtze River Delta urban agglomeration is at a high level by 2020, while the trend of Beijing–Tianjin–Hebei urban agglomeration is at a general level. Compared with the previous evaluation models, this evaluation method has a good explanation and can emphasize the consideration of dynamic evaluation. The research results annotate the current situation of road network integration of Beijing–Tianjin–Hebei and Yangtze River Delta urban agglomeration that can satisfy the requirement of urban agglomeration development. And it provides decision-making reference for further optimizing of the road network planning and layout of urban agglomeration.