Evaluating traveler costs of alternative traffic management plans at highway work zones using a dynamic traffic assignment model

This dissertation formalizes a procedure to evaluate the impacts of traffic management plans on traveler costs during major highway work. The proposed procedure is based upon the use of DYMOD, a dynamic traffic assignment program. DYMOD is used to calculate differences in travel times for alternative traffic management scenarios, and the implications of these travel times on construction costs and traffic safety are discussed. In DYMOD, queuing effects are approximated through capacity losses on links upstream of a bottleneck or a congested link. This dissertation explains the approximation of queuing effects currently used in DYMOD and proposes a better queuing approximation technique to account for how queues develop in traffic networks.; In addition to the base case, forty different work zone scenarios representing different traffic management plans were analyzed. These scenarios included three different work schedules, two levels of freeway capacity reduction, four different work zone segments, and three traffic control measures. The results suggest the following important observations: (1) the location and length of a work zone within two interchanges has a significant influence in the total travel times for all users affected by the freeway work zone; (2) closing one or two on-ramps upstream of a freeway work zone can improve or worsen total travel time depending on the severity of the work zone closure and the characteristics of streets adjacent to the work zone; and (3) the variation in travel demand throughout a day and the availability of alternative routes will determine the levels and times of closure most appropriate for a particular highway project.