A modeling procedure for the design and evaluation of automated highway system intersections and interchanges.

摘要

The Automated Highway System (AHS) is a new concept. Consequently existing modeling procedures are not appropriate for analyzing such a system. There are several special conditions that exist in an AHS. These include the automated nature of the traffic movement in the lanes, and the need for dynamic control. An Automated Highway System is envisioned as an integral part of a fully deployed intelligent transportation system.; This dissertation is focused on developing a modeling procedure for designing and analyzing intersections and interchanges of an Automated Highway System (AHS). The dissertation uses the flexibility of the existing NETSIM modeling program to develop a procedure for exploring the operational impacts of an AHS on urban streets, especially at urban intersections and interchanges. The procedure can be used to analyze the operations of an AHS, and the signalization at intersections adjacent to AHS lanes.; Three intersections layouts were modeled in NETSIM to analyze the interaction of an automated and non-automated highway system at an urban intersection. The intersections included a four-way intersection, a cloverleaf intersection, and a modified continuous flow intersection. The three models show that some modifications may be needed in both the intersection design and signalization of current intersections if they are to be used with an automated highway system. The model illustrates that it is feasible to greatly increase the volumes on a freeway lane, without impacting the flow of traffic. A greater volume can be achieved with decreased headways and platooning. The results of the model show that NETSIM is an option for analyzing an AHS. The modified continuous flow intersection preforms the best of the three intersections, based on average velocity and average delay. The other two intersections are still operational, at certain volumes, with an AHS before the delays become extensive.