Delay and emissions modelling for signalised intersections

Urban signalised intersections are usually among the worst spots in a transportation network to incur congestion and pollution, where vehicles are obliged to stop, accelerate or decelerate, thereby generating delay and emissions. Due to the dynamic nature of traffic passing through signalised intersections, this study sets out to investigate a dynamic modelling platform that can accurately and efficiently estimate delay and emissions for signalised intersections. Specifically, we study dynamic traffic models that can produce the speed profile of traffic, including the car-following model, the point-queue model (PQM), the shockwave model (SWM), and the cell-transmission model, and apply them for both delay and emissions estimation. The methods for emissions estimation from the SWM, the PQM, and the cell-transmission model are newly developed in this study. We then apply these models to an actual signalised road network in Hong Kong. This paper then compares the performances of these different models vis-a-vis their accuracy and computational requirements.