Citation

Yuan K, Knoop VL, Leclercq L, Hoogendoorn SP. Transportmetrica B: Transp. Dyn. 2017; 5(2): 145-158.

Copyright

(Copyright © 2017, Hong Kong Society for Transportation Studies, Publisher Informa - Taylor and Francis Group)

DOI

10.1080/21680566.2016.1245163

PMID

unavailable

Abstract

In freeways, the capacity drop means that the maximum traffic flow is higher than congestion discharge rates there. Various capacity drop magnitudes have been empirically observed before. But the mechanism behind this wide capacity drop range is not yet found. This contribution fills in the gap by relating the congestion discharge rates to different congestions in empirical observations. Two days' data show that the outflows of stop-and-go waves are always lower than those of standing queues. Different discharge rates, ranging from 5220 to 6040 veh/h at the same site, always accompany different congestion states. Moreover, the different observations show that a higher discharge rate means a higher density in the free-flow branch in the fundamental diagram. This contribution shows that discharging rates probably could be controlled by transforming the congestion states. For instance, transforming a stop-and-go wave into a standing queue at a bottleneck might increase the bottleneck throughput.

Language: en

Keywords

Capacity drop; congestion states; discharging rate; flow distribution; standing queue; stop-and-go wave