基于速度特性的城市快速路常发性交通拥堵研究

基于城市快速路浮动车技术,获取北京市快速路瓶颈路段全天交通流运行速度时间序列数据,对快速路常发性交通拥堵形成及消散进行精细化定量分析。首先应用小波分析技术对数据进行降噪处理,依据速度变化特性将快速路瓶颈处交通流运行状态划分为稳定运行态、拥堵形成态、拥堵态及拥堵消散态4种状态,并分析不同状态下的速度表现特征。研究表明,应用速度变化量可以判别交通流所处状态,而后利用统计学方法给出不同状态之间变化的判断阈值,并归纳出快速路常发性交通拥堵形成时刻、消散时刻及持续时间的判别方法。该方法对拥堵特性判别精度可达80%以上,对交通拥堵预测及交通管理具有明显实际应用价值。 

Recurrent Congestion Analysis Based on Speed Variation Characteristics on Urban Expressway

By using floating car technology on urban expressway ,time series speed data were obtained .The time series speed data were processed and then used to analyze and quantify the formation and dissipation of the recurred con -gestions on the bottleneck sections of Beijing expressways .First ,Wavelet analysis method was applied to reducing the noise in the time-series data .The traffic bottleneck condition can be divided into four states ,namely ,steady-state opera-tion ,formation of congestion ,congested state ,and dissipation of congestion according to the characteristics of speed vari-ation .Each traffic bottleneck state can be determined by applying the speed variation amount as the evaluation index .Sta-tistical method was used to determine the threshold from one state changing to another state .The index and threshold can be used to induct the traffic congestion formation time ,dissipation time and duration of congestion .The accuracy rate of the method for identifying traffic congestion is more than 80 percent .The method can provide significant practical benefit for congestion prediction and traffic management .