Tools and models for testing the capacity, level of functionality and performances for two-lane roundabout

Rodica Dorina Cadar, Gavril Hoda, Rozalia Melania Boitor, George Moga


Starting with the first decade of the XXth century, the first signs of interest appear for the arrangement of circular crossroads in America and in Europe as well. A history of the evolution of such types of arrangements is presented up until modern endorsements from our days.

This paper presents a case study for a two-lane roundabout, positioned in the Municipality of Cluj-Napoca, Romania. The capacity of circulation, the level of functionality and the performance of the crossroad are analysed by using the analytical and empirical models.

Moreover, the relationship between entry flow and the circulating flow is analysed, based on the observations made within 15 minutes intervals at the morning and the afternoon peaks of the traffic from the area.


roundabout capacity; gap-acceptance theory; empirical theory

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