蝴蝶领结型交叉口交通组织与几何参数计算

为消除平面交叉口左转交通对交叉口的瓶颈作用，采用蝴蝶领结型交叉口交通组织方式，禁止交叉口车辆左转，将左转车流引至次要道路的环岛处进行掉头，将左转车流变成直行车流，并根据车速、道路和交通条件推导了掉头环岛与交叉口的距离、半径和车道宽度的计算模型。经过蝴蝶领结型交叉口交通组织以后，使交叉口的车辆禁止向左行驶，促使冲突点减少且信号控制只需两个相位，能够将交叉口信号灯的利用率提升，对交叉口运行效率具有显著提升效果。

Traffic Organization and Geometric Parameters Calculation of Bow-tie-shaped Intersection

In order to eliminate the bottleneck effect of left-turn traffic on at-grade intersection, the traffic organization mode of bow-tie-shaped intersection is used to prohibit the vehicles turning left at intersection. The left-turn vehicles are led to turn round at the ring island of secondary road. The left-turn traffic is changed into straight traffic. According to the vehicle speed, road and traffic conditions, the calculation models of distance, radius and lane width between the ring island and the intersection are deduced. The traffic organization of the bow-tie-shaped intersection prohibits the vehicles at intersection to turn left. The conflict point is reduced and the signal control is only two phases. The utilization rate of signal lamp can be improved at intersection, and the operation efficiency of intersection has the remarkable improvement effect.