不同交通供需分布下的路网畅通可靠度变化规律研究

畅通可靠度是在研究交通供需之间关系的基础上提出的概率型指标。根据畅通可靠度的计算方法,将各小区交通需求和各路段通行能力视为符合正态分布的变量,通过组合不同交通供需分布方式,对所需要研究的路网采用多次随机试验的方法得到各道路单元、路径及系统的畅通可靠度,并研究不同交通供需分布方式对路网车速和畅通可靠度的影响,寻找在不同交通供需下道路畅通可靠度的变化规律。分析表明:道路单元、路径、OD对间及路网的畅通可靠度变化规律是一致的,并且畅通标准越高,路网的畅通可靠度就越低;在同一畅通标准及相同的需求变化范围下,需求越低,相应的畅通可靠度会越高;同时,随着畅通标准的提高,道路通行能力和交通需求方差越大,道路畅通可靠度也越大。

Research on Unblocked Reliability of Road Network under Different Traffic Demand and Supply Distribution

Unblocked reliability is a probability index,which reflects the relationship between traffic demand and supply in peak hour at workday.Regarding traffic demand and road capacity as variables conforming to normal distribution,the different road network unblocked reliability can be gotten by the random experimentation,and the change rules of road network unblocked reliability and velocity under different supply and demand combination are put foreword.The road network unblocked reliability analyses show that the change rules of road components,routes,OD,and network are alike;the unblocked criterion is higher,the unblocked reliability is smaller;the traffic demand is lower,the corresponding reliability is higher under the same unblocked criterion and the same demand variation.