Abstract:
This paper presents the conceptual framework for a sketch planning approach for evaluating the in emissions and vehicle operating costs associated with isolated traffic control devices. Current practice is to use traffic simulation models to evaluate the emissions effects of traffic control devices. Simulation models are data intensive and complex to use. Simulation models may not adequately represent certain traffic control devices. The proposed sketch planning tool combines spreadsheets, basic traffic flow theory, real world speed and emissions data, and recent research sponsored by the National Cooperative Highway Research Program to estimate both emissions and operating costs associated with stop signs, isolated traffic signals, roundabouts, and paired intersections such as those that exist at interchanges. The tool may be used in preliminary evaluation of traffic control devices, calculation of emissions for congestion mitigation air quality funding, and perhaps for conformity analyses of projects in rural areas.
