Using Simulation Models to Assess Impacts of Highway Work Zone Strategies: Eight Case Studies along Interstate Highways and State Routes in New England.

As the National Highway System reaches the end of its serviceable life, transportation agencies increasingly need to focus on the preservation, rehabilitation, and maintenance of these roads. In light of significant increases in the amount of work zone activity, transportation officials and contractors are challenged with finding ways to reduce the negative impacts on driver mobility. The key to addressing this challenge is to recognize potential impacts well in advance. One major tool used for this purpose is computer simulation. There are many simulation models in existence, someof which are designed specifically for work zone analysis. Examples of these models include QUEWZ, QuickZone, CORSIM, and CA4PRS. QuickZone and QUEWZ are designed to estimate delays, queues, and delay-related costs associated with traffic impacts created by work zones. CORSIM is a user-friendly graphics post-processor that displays traffic networks, animates simulated traffic flow operations, animates and displays simulation output measures of effectiveness, and displays user-specified input parameters for simulated network objects. CA4PRS estimates the maximum distance of highwaythat can be rehabilitated or reconstructed with various project staging plans and resource constraints. This paper includes case studies that illustrate and evaluate these models in terms of their ease of use, data requirements, and ability to simulate and assess work zone strategies, sheddinglight on the relative reliability and accuracy of these simulation modelsas well as their user-friendliness and data requirements. This paper compares simulation results to actual work zones conditions in eight locations across New England. The results of this evaluation will be of interest to State and local transportation engineers responsible for planning and designing work zone strategies. This research has shown that simulation provides a low-risk, low-cost environment in which to test and analyze a variety of work zone alternatives. Care must be taken, however, in using simulation results to make concrete decisions. It is strongly recommended that users of these simulation models have a fundamental understanding of highway capacity analyses and traffic flow fundamentals. Users must trust their intuition and use their knowledge when results appear to be out of theordinary. Simulation does, however, give the transportation world a better understanding of the impacts of highway work zone strategies.