城市道路路段旅行时间的特性分析

Property Analysis of Urban Road Travel Time

了解路段旅行时间随交通状况变化特性对利用探测车等新式交通检测技术估计交通状态非常重要.基于交通微观仿真模型,分析了路段旅行时间随交通状况的变化特性,验证了平均路段旅行时间是否能够采集通畅、拥挤到堵塞这三个状态,以及是否能细分这三个交通状态.结果表明:(1)平均路段旅行时间能够判断上述三个状态;(2)在拥挤阶段,随着交通状态恶化,平均路段旅行时间逐步增加,因此能够细分拥挤状态为多个子状态,但由于在通畅阶段,即便流量增加,平均路段旅行时间基本不变,因此无法细分通畅状态,细分通畅状态需要流量信息;(3)路段旅行时间在拥挤状态时处于双峰分布,难以用少量的探测车提供的数据可靠地估计平均路段旅行时间.

To estimate arterial link traffic condition based on probe vehicles,it is necessary to investigate the fluctuation characteristics of road travel time with traffic condition.On the basis of micro traffic simulation model,this paper analyzes the fluctuation of road travel time with traffic condition,and examines whether the mean travel time can reflect the variation of traffic conditions including free flow,congestion to traffic jam.As a conclusion,（1） mean link travel time can be used to identify free flow,congestion,and traffic jam;（2） mean link travel time divides congestion condition,but cannot subdivide free flow condition;（3） in the condition of congestion,travel time is distributed as a two-peak mode,and the average travel time is difficult to be estimated by small size sample.