A New Lane-Based Model for Platooned Patterns at Closely-Spaced Signalised Intersections

Aerial photograph of road

Abstract

An analytical lane-based method for determining platoon patterns at closely-spaced signalised intersections is discussed. The method has been developed for the SIDRA INTERSECTION software. The traditional network models using "links" or "lane groups" based on aggregation of individual lane conditions cannot provide sufficient information about departure and arrival patterns, queue lengths, lane blockage probabilities, backward spread of queues, and so on at a lane level. These are important in modelling signal platoon patterns for estimating performance measures (delay, back of queue, stop rate). This is particularly important in evaluating closely-spaced intersections with high demand flows where vehicles have limited opportunities for lane changing between intersections. The new lane-based method derives second-by-second downstream arrival patterns in accordance with above requirements. Modelling of departure patterns at upstream lanes takes into account (i) probabilities of blockage by downstream queues and the resulting capacity reductions at blocked upstream lanes, (ii) capacity constraint at oversaturated upstream lanes resulting in reduced downstream arrival flows, and (iii) lane choices of movements from approach lanes to exit lanes at the upstream intersection (lane movements). The modelling of arrival patterns at downstream approach lanes takes into account implied midblock lane changes. The model is expected to improve assessment of signal coordination quality and optimisation of signal offsets. A detailed example is presented using various analysis scenarios to demonstrate important implications of the lane-based model.

Reference

AKÇELIK, R. (2014). A New Lane-Based Model for Platooned Patterns at Closely-Spaced Signalised Intersections. Paper presented at the 26th ARRB Conference, Sydney, Australia, Oct 2014.