Queues at Junctions Controlled by Traffic Signals

摘要

The results are presented of an on-site study of traffic queueing in sections of a signal-controlled network. Almost 500 queues at three different sites have been extensively analyzed using statistical methods. Two simple formulations have been derived so that queue lengths can easily be predicted (a) if the percentage of heavy vehicles is known or (b) if the traffic signal pcu equivalents of vehicles in the queue are known. One pcu is shown to occupy 5.76 + or - 0.05 meters in a stationary queue. The average spatial gap length between vehicles in a queue was found to be 1.52 + or - 0.06 meters and at all but one site studied the first vehicle on average stopped 1.1 + or - 1.1 meters behind the stopline. There is no indication that heavy vehicles queue closer together than light vehicles, that vehicles on steep downward gradients have shorter gap lengths, or that the composition of vehicles queueing is different from vehicles not queueing.