关于城市轨道交通线路合理长度的讨论

我国城市轨道交通线网的规划建设中出现了一些长度超过50km的超长线，以及分期工程初期线路长度较短的线路，这些线路在运营时可能会暴露出一些问题。从需求特征出发，分别对超长线和较短线存在的问题进行分析。如果线路超长，各线段的需求特征、功能定位和客流量级有较大区别，给线路的系统选型、运营组织均带来困难。而较短线不能满足出行需求，将使客流量和运营效益受到很大影响。最后提出一般情况下城市轨道交通线路长度在15～35km较为合理的建议。

Discussion on the Reasonable Length of an Urban Rail Transit Line

In the process of urban rail transit planning and construction in China,there were some overlong lines whose lengths exceeded 50 km while short lines were also built in the early phases,which will probably cause problems in operation.Based on the characteristics of passengers' actual demand,this paper analyzes the problems for both overlong lines and short lines respectively.If a line is too long,the demand characteristic,function and passenger volume for each section of it will be very different,that it is hard to select train types and to operate.The short lines are inconvenient for passengers and cannot satisfy the trip demand,thus the passenger volume and revenue will be negatively affected.In the end,this paper presents relevant opinions on the reasonable length of an urban rail transit line.