Citation

Brilon W. Transp. Res. Circular 2005; 2005(E-C083): 15p.

Copyright

(Copyright © 2005, U.S. National Academy of Sciences Transportation Research Board)

DOI

unavailable

PMID

unavailable

Abstract

Today, Germany has 15-years of experience with different kinds of modern roundabouts. In addition to that, large conventional roundabouts have been used for 70 years. Modern roundabouts include compact single-lane roundabouts with diameters between 26 and 40 m; mini-roundabouts with a traversable island and diameters between 13 and 25 m; and larger roundabouts (40 -60 m) with 2-lane access for cars and single-lane operation for trucks. All these types turned out to be very successful regarding both traffic safety and capacity. On the other side the traditional larger 2-lane roundabouts have significant safety problems. The paper describes the German experience from a long series of research projects regarding traffic safety, capacity, and traffic performance estimation as well as geometric design.