平面交叉口禁止左转效应分析

合理组织平面交叉口中的左转车流问题,与行车安全和通行能力有直接关系。禁止左转是平面交叉口组织的一个重要方式,它可能带来的交通效应与多种因素有关。从左转的交通特性出发,研究禁止左转后交叉口延误变化的机理和交通流的重新组织方式,得到禁止左转后交叉口延误变化的计算模型。通过模型分析认为,交叉口饱和度、路网密度和左转车流比例是影响交通效应的重要边界条件,并分析了这些边界条件对于禁止左转产生效应的影响方式。

Analysis of Effects of Left-Turn Prohibitions on at-grade Intersections

Reasonably organizing the left-turn flow at the at-grade intersection can directly impact the driving safety and road capacity. Left-turn prohibition is an important approach to organizing the surface intersection, and its effects are relevant to many factors. Based on the characteristics of the left-turn traffic flow, this paper analyzes the mechanism of intersection delay change after the left-turn is prohibited. Through reorganization of the traffic flow while left-turn is prohibited, a computing model for intersection delay change is developed. Through the modeling analysis, it finds out some important boundary conditions including intersection saturation, network density and left-turn ratio. Meanwhile the paper analyzes the way these boundary conditions impact on the left-turn prohibition effects.