Forecasting Sustainable Urban Transport Demand for Management and Improving the Safety of Routes by System Dynamics: A Case Study of Tehran.

A feature of today’s urban growth is the increasing density of population, the people in urban zone often deal with the travel demand in order to carry out daily activities. In general, travel demand by private transport is higher than public transport such as subway and bus in Tehran, that identify as problem. Additionally, due to the high demand for private transport, the number of injuries, accidents, and fatalities would be high. Thus, improving the safety of citizens on the urban routes is critical. In present study, the system dynamics is proposed to investigate the behavior of variables that affect the transport modes demand. The structure of system dynamics model for forecasting travel demand consists of four subsystems including population, travel demand, investment in transport infrastructure, and traffic congestion. Based on subsystems, the stock and flow diagram is built. After implementing mathematical equations, the model is simulated, and finally, it is validated. In this regard, several policy scenarios are considered to increase the demand of public and rail transport as well as to reduce demand for private transport such as 1) controlling public transport fare, 2) controlling rail transport fare, 3) increasing investment in public and rail transport and 4) controlling fuel price. According to this study, controlling fares and fuel price are more effective policies for travel demand management and improving safety of routes.