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This report summarizes the results from the technical support and testing of the freeway traffic simulation software developed at the University of Minnesota. The University's Civil Engineering Department developed and implemented an experimental course that addressed fundamental theories in traffic flow modeling and simulation. They also incorporated a set of an online help manual into simulation software. Software testing was conducted through two sets of case studies involving the high-occupancy vehicle (HOV) lane and ramp metering simulation modules. The HOV lane case study used a 10-mile section of the westbound I-94 freeway with an additional lane and evaluated the performance of alternative HOV lane strategies with different sets of demand and HOV proportions. For the same amount of total demand without assuming induced trips, the higher the HOV proportion, the smaller the mainline delay. The ramp metering case study compared the performance of the current Minnesota Department of Transportation metering policy with that of a no-metering option for a 16-mile section of the northbound 169 freeway with 20% higher demand than the current level. The metering case study showed that the total system delay, including both mainline ramps, was significantly reduced when the ramps were controlled compared to a no-metering case for a given set of demand. The case studies indicate that the simulation software can be applicable in evaluating alternative design and operational strategies for a given set of demands.

This report summarizes the final results of the research effort to develop a freeway traffic simulator with the capability to evaluate freeway operational strategies, such as traffic-responsive ramp metering and high-occupancy vehicles (HOV) lanes. Researchers first developed an efficient software data structure by adopting a dynamic memory allocation scheme to use the available memory as efficiently as possible. That work also included modifying the existing macroscopic, segment-based modeling structure and developing new types of pipeline segments to facilitate detection modeling and further model enhancements. Based on the new segment-based modeling structure, researchers developed a new simulation module to handle HOV lane traffic flows and extended the simulation procedure for an exclusive HOV lane to handle a network of freeways. Further, the simulation model also incorporates a new module to emulate the traffic-responsive ramp metering algorithm implemented by the Traffic Management Center since the 1980s. The new software structure developed in this research allows the future addition of new metering algorithms without major difficulties. To facilitate the data input process for the expanded simulation features, a new Windows-based user interface was developed using the Delphi software development tool kit. With the new user interface, most of the data input process can be done without exiting the main menu screen. Note: The phase I report is available at https://hdl.handle.net/11299/156893.