Analysis of Traffic Operation Performances at Roundabouts

Abstract

The traffic operation performances at roundabouts are complicated under the influence of confluence operations. On the basis of the Mengxi square in Zhenjiang city roundabouts survey using video cameras, some parameter performances of different vehicle types on weaving sections and circulating lanes are analyzed, which included the velocity distribution, the gap distribution, as well as the distance distribution of lane changing. Based on the analysis, some of the conclusions are as follows: 1) The vehicle velocity of inner circulating lane is larger than the outer circulating lane 2) The entry vehicle velocity is smallest 3) The distribution of entry gaps is different from circulating gaps 4) the characteristics of vehicle teams are mostly same in different lanes 5) When the type is bigger, the lane changing distance is smaller 6) For the same type, the distance of lane changing shows ladder-like distribution.The research result will be a base for improving the capacity of roundabouts.