快速路合流影响区交通安全影响研究

Study on Effect of Expressway Confluence Affecting Zone on Traffic Safety

为解决合流影响区对道路交通安全的影响,本研究以分析合流区的交通流特性和通行能力为出发点,通过HCM2000的理论计算和微观仿真的方法,与采集的观测数据结果进行对比,验证仿真结果的可行性,探讨匝道分流流量、减速段长度与分流影响区密度的关系,以4车道和6车道为例进行分析匝道分流流量、减速段长度与分流影响区密度的关系。结果表明,车道合流区密度随着合流与上游流量比例的增大而增大,在同样的分流合流与上游流量比下,4车道合流区的密度要比6车道小,并且两者都呈指数形式的增长;车道合流影响区密度随着加速段长度的增大而减小,当加速段长度为170m时6车道合流区的密度比加速道长度为150m情况下要大。当加速段长度大于240m时,车流密度下降趋势逐渐趋缓,且4车道与6车道的车流密度比较接近。

This study was carried out to analyze the traffic flow characteristics and traffic capacity in con- fluence affected zone as a starting point to avoid the influence of confluence affected zone on expressway traffic safety,the relationships between the flow of ramp split flow, length of feasibility deceleration and density of shunt-affected zone were discussed through HCM2000 theoretical calculations and microscopic simulation method, finally, the collected and observed data were contrasted to analyze the relationships be- tween the flow of the ramp split flow, the feasibility deceleration length and shunt-affected zone density of the four lanes and six lanes. The results showed that the density of the lanes confluence area increased with the increase of ratio of confluence flow and upstream flow,under the ratio of flow from split flow and up- stream, the density of the four lanes confluence area was smaller than that of six lanes confluence area, and the both were inceased by index number type. The density of expressway confluence affected zone de- creased with the increase of the feasibility deceleration. When the length of the feasibility deceleration was 170 m,the density in the confluence zone of six lanes was bigger than that under the condition of 150 m. When the length of the feasibility deceleration was greater than 240 m, the traffic density gradually de- creased and the traffic density in four lanes and six lanes was comparatively close to each other.