Progression Factor for Queue Length and Other Queue-Related Statistics

Abstract

A method is presented that extends the U.S. Highway Capacity Manual (HCM) delay progression factor method to the prediction of queue length, queue clearance time, proportion queued (stopped), and queue move-up rate. These predictions are achieved by the introduction of an additional progression factor and adoption of the HCM overflow term adjustment factor, providing a simple method to allow for the effects of platooned arrivals on the performance of coordinated signalized intersections. The method is useful at the level of basic capacity and performance analysis of a single intersection where detailed platooned arrival patterns generated at upstream signal stop lines are not available. The arrival types defined by the HCM as the basic input to define the characteristics of platooned arrivals are adopted for use in calculating the additional progression factor in the same way as the original HCM progression factor for delay. It is assumed that the reader has a good knowledge of the subject area.