Nowadays, in modern cities, travel demand management policies are more effective solutions for reducing vehicle traffic than road construction and private transportation infrastructure development. Traditional transportation planning methods that are appropriate for a partial analysis in traffic area zone levels require extensive data collection and only could be used to evaluate and compare a few number of demand management policies with limited criteria. In this paper, system dynamics modelling has been used to evaluate transport demand management policies. System dynamics is a suitable method for long-term macro-scale evaluations of different policies with various indicators, because in this method, causal relationships between variables and their feedbacks are considered as well as its dynamic approach, not needing detailed information in traffic area zones (TAZ) level, and the possibility of evaluating different policies. In this research, encouraging policies like improving the bus and taxi services, completing metro network development, improving bicycle facilities and encouraging to carpool as well as restrictive policies like cordon pricing policies, increasing parking prices, and odd-even policy and also simultaneously applying some of the encouraging policies and effective restrictive policies in the form of a policy package are being investigated in the central business district of Isfahan city. Urban transportation causal loops were conceptualized and the dynamic relations among urban transportation variables were created to develop the pertinent urban dynamics model. Efficacious transportation policies, which will be implemented for ten years, will be ranked in accordance with monitoring three indicators of air pollution, energy consumption and traffic mobility. Respectively, completing metro network development, BRT network development, improving bicycle facilities, cordon pricing, increasing parking prices, improving bus services, improving taxi services, odd-even policy, and encouraging to carpool are the most effective policies in Isfahan CBD. Among combined policies, completing metro network development simultaneously with cordon pricing has been the most effective combined policy to decrease air pollution and energy consumption and to increase traffic mobility in future.
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