Employment of the Traffic Management Laboratory (TRAMLAB) for Evaluating Ramp Control Strategies in the Twin Cities

Project summary:

As freeway traffic congestion spreads, ramp metering is implemented to address the problem. However, excessive ramp delays are provoking increasing opposition to freeway ramp control. The objective of this research was to employ a recently developed tool called the Traffic Management Laboratory (TRAMLAB) for assessing the effectiveness of MnDOT's control strategy in three Twin Cities freeway sections totaling approximately 65 miles. The feasibility of a corridor simulation was followed by the selection and preliminary model development of the combination of an arterial and a freeway in the Twin Cities. As a result of this testing, TRAMLAB evolved into an effective tool for developing control strategies that could reduce ramp delays without excessively increasing freeway congestion. Finally, this research contributed to the development of a new traffic management concept for early detection of incident prone traffic conditions, suitable for integration into traffic management through Ramp Metering and Variable Message Signs in order to smooth flow and prevent (to the extent possible) incident occurrence, thereby further reducing delays and improving safety. Although this project focused on evaluating ramp metering and implementing a concept recently developed in a current project, the research also addressed the more general issue of research continuity and suggested a strategic partnership with MnDOT.