The Warrant of Slip Lane at Single-Lane Roundabout

摘要

In the NCHRP Report 672, a brief introduction is given to the right-turn slip lane at a roundabout, and the lane capacity is derived. On this basis, we considered the setting mode of two types of slip lanes, such as free driving (Free Flow, FF) and yield driving (Yield, Y). The traffic flow characteristics were analyzed under the conditions of its setting. A large number of scenes were designed by VISSIM simulation, taking the average vehicle delay as the index. A comparison of operation was conducted between with and without slip lane, under the combination of different traffic flows and right-turn ratio. The critical conditions of different setting modes were preliminarily discussed. Considering the impact of slow traffic such as pedestrians and bicycles, the next research plan was put forward.