Multimodal Use of Roundabouts, Application in Paris
A Torday, TSS-Traffic Simulation Systems, ES
Roundabouts have an historic role in improving safety, reducing congestion and delays at junctions. They are safer because of slower speeds and a reduced number of conflict points ? spots where vehicles may collide with each other or with pedestrians.
Although these roundabouts must have been initially designed to offer the best level of service, the increase of traffic can generate unexpected congestion at the approaches or within the roundabout.
Under these circumstances current layouts and control plan settings need to be adjusted in order to accommodate the new traffic demand.
Such adjustment might also be required as society now plebiscites green modes of transport for urban journeys and roundabouts are no exception. Pedestrians and cyclist have to be considered. The efficiency of the roundabout now depends on how these different modes of transport can be integrated in the most safely and reliable way.
Plans to these roundabouts can also accommodate and adapt at slower mode.
In urban area these roundabouts are also the public place where local life is expressed and developed: businesses, education, culture, social activities, etc. Furthermore,
3 examples in Paris are presented in this paper:
? Improvement of the Place du Maréchal Juin, an existing roundabout of a popular square in Paris. The objective was to reduce congestion and to protect the pedestrians in the roundabout.
? Place Leon Blum , diagnostic of the roundabouts
? Insertion Tramway extension Maréchaux Est
These three projects were undertaken for la Mairie de Paris. Microsimulation models were conducted to test and adjust such changes.
It was shown that significant improvements were achieved by simply adjusting control plan and coordinate traffic lights between each other.
Association for European Transport