Unsignalized Intersections in Germany - a State of the Art 1997

Research results on the field of unsignalized intersections from Germany were of some importance for practical application in the past also in other countries. Since the first two international workshops in 1988 and 1991 some progress has been made on some aspects of theory for TWSC intersections. This paper tries to provide short descriptions of those new ideas which might be of more general interest. Thus contributions on the following fields are described: two-stage priority, flared minor street entries and short lanes, as well as formulas for impedance factors. For roundabouts the following items are explained: current capacity formulas based on empirical linear regression technique, a more universal gap-acceptance technique for roundabouts, capacity reduction by pedestrians on Zebra crossings in entries and exits of roundabouts. Also experience from practical application of roundabouts is mentioned, like principles of design, safety, and experiments with miniroundabouts. The paper gives a brief explanation of the topics mentioned and makes reference to some of the publications where these issues are explained more comprehensively.