Modelling And Analysis Of Tradable Credit Scheme Based On The Hoterogeneous

With the rapid development of economy, traffic demand increases seriously. At the same time, urban traffic congestion has become an important and common issue in many cities. Traffic congestion brings many urban development problems, such as decreasing the urban transportation network capacity and giving rise to environmental pollution severely. However, the traditional expansion of city traffic network to increase network capacity is in conflict with the limited land resources in the city, which cannot meet the users’requirement radically. Although the expansion of the network alleviates the network congestion temporarily, it attracts more traffic flow, which makes the traffic problem back to the beginning. Therefore, we start from the demand management, with the scheme of tradable credit to limit the ways to improve the network operation efficiency and to integrate and optimize transportation resource. Because of the differences in economic background and social features of the network travelers, they play different roles in traffic network. Practically, we give a model and analysis of tradable credit scheme based on the heterogeneous to solve the above problems.The main work of this paper includes the following three parts:In the first part, this thesis introduces the current situation and influence of traffic network, studies and analyzes the reasons of network congestion, and compares the advantages and disadvantages of different mitigation strategies from the perspective of demand management.In the second part, a mathematical model is established according to the user equilibrium principle and the system optimum principle, taking both the users’ characteristics and the scheme of tradable credit into consideration. Models will be set up from the static and the dynamic perspective, with description and analysis for different situations. Matlab algorithm is used to assign traffic demand for vehicles in the static model, and to calculate the credit consumption rate in the network equilibrium state according to system optimal conditions. By establishing the dynamic model, it proves the unity of credit charge in the case of heterogeneous and the evolution process from non equilibrium state to equilibrium state.The third part is the practical examples, in which the total travel cost and credit charge rate in each network path is calculated by numerical example both in the static model and dynamic model under a given network and fixed demand condition. Case studies, which verifies the feasibility and stability of the network, offers the theoretical foundation for the urban traffic planning and administration. It is beneficial to narrow the gap between theoretical research on tradable credit scheme and its practical application.