基于出行不均匀分布的通达型公交网络

An Accessible Bus Network with Uneven Travel Distribution

通达性公交网络具有时空覆盖率高,乘客出行时间短等优点,可有效缓减城市交通拥堵。本文面向市中心靠近城市边界的城市形态且出行需求空间分布不均匀的城市,假设市中心出行均匀分布,郊区出行为线性递减的空间需求函数,建立公交线网规划、站点和频率设置的综合模型。模型受决策变量和输入参数影响小,稳定性和可行性好。当车头时距、市中心与城市比例、公交站距变化范围在-50%~46%,总成本增加不超过10%。乘客步行速度对总成本和乘客的成本影响较大,发展共享单车、公交微循环等会显著降低乘客出行成本。需求越集中于市中心,公交公司成本越会显著下降,但公交系统的稳定性下降,会削弱公交竞争力。

An accessible bus network is featured of good time and spatial coverage and reduced passenger travel time,which is helpful for traffic congestion mitigation.This study focuses on cities that has its downtown area located near the city boundary and the travel demand is unevenly distributed in the city area.Assuming the travel demand function is uniformly distributed in downtown area and linearly decreased in suburban area,this study develops a model for planning bus network and determining bus stations and departure frequencies.The model is not significantly affected by the decision variables and input parameters,and has good stability and feasibility.When the headway,the ratio of downtown area to the city area,and the stop spacing varied from-50%to 46%,the system cost would increase by less than 10%.The passenger access speed has a great impact on the system cost and the user cost.This indicates that promoting shared bicycles and bus microcirculation would significantly reduce the cost of bus travel.The more demand was concentrated in downtown,the bus agency would have significantly reduced operation cost.However,the stability of the bus network would see a decrease,which would also weaken the competitiveness of the bus.