Conceptual Framework for Discrete Event Simulation of Interstate Traffic

This paper presents the development of a conceptual framework for simulating interstate traffic. ProcessModel was selected as the simulation package. The framework has been successfully used to model interstate I-65 from Montgomery to Birmingham, AL. The study corridor begins near the Alabama River Bridge north of downtown Montgomery at mile marker 172 and extends north to mile marker 234 near Alabaster and the southern Birmingham suburbs. The conceptual framework provided an excellent template in the rapid development of interstate traffic ProcessModel. The framework greatly reduced development time, model debugging and verification and validation. Using the conceptual framework it is possible to construct the model in pieces, or one segment at a time. Consequently, each segment can be debugged and verified separately thus reducing development time. A similar interstate traffic model using CORSIM has been developed and compared very favorably with the ProcessModel results. For basic planning applications of longer rural freeway corridors that do not have complex lane drops or significant merging issues, ProcessModel may be a useful tool to indicate when traffic congestion may occur in an existing or future condition. However, when detailed analysis is needed at a specific interchange or in urban areas where lane changing and ramp merging and weaving are more pronounced, CORSIM may be a better alternative. Included in this paper are a description of the modeling framework, description of the application implementation and conclusions.