Ph.D Thesis

Ph.D StudentJuran Ido
SubjectImprovement of Dynamic Work-Zone Operations
Using ITS
DepartmentDepartment of Civil and Environmental Engineering
Supervisors ASSOCIATE PROF. Ilan Ishai
PROF. Joseph Prashker (Deceased)


This research presents the first model that can assess and explore the impacts that moving bottlenecks, such as slow moving conveys, have on a traffic network.  The model is essentially a new dynamic traffic assignment model that can evaluate the network delays imposed by the moving bottlenecks and determine optimal traveling paths to minimize them.  These paths may serve as the basis for route guidance plans in the context of ITS.

The model was formulated as a bi-level mathematical optimization program.  The proposed algorithmic solution incorporates an enhanced mesoscopic simulation that captures traffic dynamics in a more realistic way than existing analytical and mesoscopic simulation models while respecting all the constrains of a dynamic transportation network.  The main improvement offered by the simulation over existing mesoscopic simulation models is that it allows the traffic density and speed to vary along the road.  This is valuable for two reasons.  First, in this way the developed model can be consistent with the causality principle of traffic flow, and secondly the model allows the assessment of the special dynamic constraints of a moving bottleneck.

The research presents two experimental studies. The first was conducted in order to verify the validity of the model while the second was carried out in order to derive insights regarding the impact of a moving bottleneck on network performance.  A conceptual investigation has been performed on two theoretical sample networks as well as on the actual Tel Aviv metropolitan network.  The experiments showed that the developed model performs well and the overall results are consistent with previous studies. In addition, the results showed that the model yields a reasonable forecast regarding the impact of a moving bottleneck on traffic flow.