城市轨道交通规划线网生成模型研究

Research on generation model of urban rail transit planning network

建立城市轨道交通线网规划阶段的线网定量化生成数学模型,模型在考虑提高轨道交通客流分担竞争力的基础上,以线网平均负荷强度最大为目标,以线网拓扑关系、节点和区间重复度、线路条件、客流平衡、换乘条件、线网规模、舒适度水平为约束;提出以城市主要客流走廊和客流集散点为基础的确定线网搜索范围和搜索方向的策略,合理把握线路的走向边界;由于该问题属于NP-Hard问题,对于大型网络搜索空间大,难以求解,文章基于模拟退火框架设计邻域搜索算法求解方法。以X市为例,计算得到该市轨道交通远期规划线网各线路走向,通过与X市既有规划线网的对比分析,可以看出,基于本模型生成的规划线网,在满足主客流走廊和城市发展主轴方向的客流需求下,具有规模小、线网利用率高的特点,从而验证模型与算法的有效性。

A mathematical model for quantitative generation of urban rail transit planning network is established in this study. The model is developed in consideration of enhancing the competitiveness of passenger flow sharing for rail transit, targeting at maximizing the average load intensity of the network with the network topology, node and section repeatability, line conditions, passenger flow balance, transfer condition, network scale and comfort level as constraints. Based on the main passenger corridors and passenger distributing centers, a strategy for determining the search range and search direction of the network is proposed to limit the trend boundary of the alignments reasonably. The problem belongs to NP-Hard problem, which is difficult to be solved for the large-scale network due to its large search space. So, a neighborhood search algorithm is designed based on simulated annealing framework. With the X city taken as an example, the routes of the rail transit network in the long-term are calculated. Compared with the existing planned network of the city, the network generated based on the present model has smaller scale and higher utilization rate while meeting the passenger demand along the main passenger corridors and main axis of urban development, thus verifying the effectiveness of the model and the algorithm.