Dynamic Modeling of the Traffic of Metropolitan Cities for Presenting Transportation Improvement Policies (Case Study: Metropolitan Tehran)

The growing trend towards urbanization has caused problems that, in some cases, are quite complicated. A major problem, especially in large cities, is the traffic. Considering the effects of traffic on different aspects of people’s lives, and the importance of commutation in urban life, specifying traffic relaxing and control policies and strategies becomes very crucial.Different methods exist to analyze different levels of traffic. Traffic is a complicated problem with a lot of feedback behavior which is a function of different elements. Many experts believe that urban commutation is a dynamic system with many influential elements. Thus, its analysis can be a suitable method to analyze and evaluate the results of traffic policies. The purpose of this article is to analyze the problem of traffic based on the causal dynamic model and to simulate its behavior to propose traffic relaxing and control policies using computer. Here, we have chosen Tehran as our case for study.In this research, traffic has been analyzed, at macro and strategic level, using dynamic modeling in the form of system dynamics analysis. First the important aspects of the problem have been specified. Then, the dynamic assumptions have been presented and the causal model constructed. Next, the behavioral credibility has been verified by the available statistics using inter-variable mathematical functions and simulating the models in the "Venism" environment. Then, certain policies have been presented (for the city of Tehran) and evaluated by software simulation. Finally, the one that can control and reduce Tehran’s traffic most effectively has been presented as the executable policy.