Research on Calculation Method and Expansion Strategy of Urban Road Network Capacity

Nowadays, with the increasing number of private cars, traffic congestion is getting worse, and the balance between traffic supply and demand is continuously tilting. Therefore, it is an urgent need to keep urban road network capacity, which indicates traffic supply to a great extent, in line with the rising traffic demand. In this paper, the definition of urban road network capacity was given from three levels systematically, including ideal capacity, real capacity, and service capacity. Then, since OD distribution is usually hard to collect, a practical and efficient algorithm for determining network capacity based on macroscopic fundamental diagram was proposed. Furthermore, we put forward strategies for the expansion of network capacity from three different aspects and demonstrated the performance with the use of three network examples. This research provides operational insights and guidance for urban road network capacity expansion and traffic congestion relief in the future.