基于建设成本约束的公路网结构演化研究

通过简化公路网系统，建立了公路网结构自组织演化框架，对演化过程进行了 仿真研究.首先，在给定各城市社会经济状况条件下，研究各城市节点间的连接概率，建立 初始路网；然后，在初始路网的基础上，通过交通分布和分配获得各道路的饱和度；最后， 以降低出行时间为目的，在建设成本最小的约束条件下，通过扩大路网规模或提高道路 等级，更新路网结构.本文以一个城市圈为对象，对路网演化过程进行了仿真.研究发现， 路网规模和等级更新存在一定的规律，城市圈内部的道路等级高于外部，且不相邻城市 间的道路等级一般较低.

Self-organization of Roads Network Structure Based on Restraint of Construct Cost

Through simplifying the roads network, this paper designs the road network structure self-organization frame by simulation methods. First, under the given conditions of each city’s socio-economic state, it analyzes the connection probability among the cities and established the initial network. Then, based on the initial network, it obtains the saturation of each road through traffic distribution and assignment. Finally, for the purpose of reducing the travel time, under the constraints of minimum construction cost, the road network is updated through expanding network scale or improving road hierarchies. Taken a city circle as an example, the paper simulates the evolution frame of road network. The result indicates that certain rules are present during updating of road network scale and hierarchies. The road hierarchies internal are higher than the external on the circle, and hierarchies of road between noncontiguous cities are always low.