Variable lane assignment provides a way of optimizing the capacity of existing roads by using dynamic devices that affect vehicle flow by selectingthe number of lanes that are open or the types of vehicles which are authorized. French experience began in the 1960s. Today, two important trials are currently under way in the Paris region and the Grenoble conurbation. The principle is straightforward and promising, using the space reserved for the emergency hard shoulder for vehicles other than emergency and maintenance vehicles. In the Paris region, the trial consists in opening the hard shoulder to traffic using automatic moveable barriers during peak periods. Opening an additional lane has a direct impact on the upstream and downstream sections. The aim of the trial is therefore to check that the gains are not local but overall (the common section and the area influenced byit) in terms of both time and safety. In the Grenoble conurbation, recurring peak period congestion on the A48 delays the coaches that operate on aregional high level of service route that ends in the city centre. The trial developed with the Council of Isere District consists in allowing the public transport vehicles to use an emergency lane when this is justified by operating conditions (traffic levels and traffic conditions). For the covering abstract see ITRD E139491.
Samenvatting