Final design after adjustment process.

As urbanization accelerates, urban public transportation systems are tasked with meeting the growing demand for travel. According to statistics, the regional rail transit network currently handles 60% of the passenger volume for trips originating from around the stations, and this is projected to increase by over 20% within the next decade. However, the current feeder bus services suffer from insufficient coverage, leading to inconvenience for passengers and impacting the overall efficiency of the transportation system. To enhance the public transit service coverage along a rail transit corridor, this study designs feeder bus services to connect the rail stations. A theoretical trunk-feeder transit design problem is firstly solved to furnish the initial feeder bus line designs. The objective is to minimize total generalized system cost with respect to the density of feeder bus routes and their service frequencies. The idealized design of the optimal bus route density function is then discretized into specific locations and fine-tuned with Geographic Information System (GIS) tool. Considering local conditions like road network and demographic information, a four-step adjustment strategy is proposed to furnish the implementation-ready design of feeder bus services. Numerical results show the final design renders at least 3.5% saving in total system cost. This study illustrates how the state-of-the-art theories of transit design can be applied into practice and highlights the connection between theoretical studies and practical application.

随着城市化进程持续加速，城市公共交通系统肩负着满足日益增长的出行需求的重任。据统计，当前区域轨道交通网络承担了车站周边出发客流的60%，预计未来十年这一占比将提升超20%。然而，当前接驳公交（feeder bus）服务覆盖不足，不仅给乘客出行带来诸多不便，更降低了整个交通系统的整体运行效率。为提升轨道交通沿线的公共交通服务覆盖范围，本研究设计了衔接轨道交通车站的接驳公交方案。首先通过求解理论干线-接驳公交设计问题，得到初始接驳公交线网方案，优化目标为以接驳公交线网密度与服务频率为决策变量，最小化系统广义总成本。随后将最优公交线网密度函数的理想化设计离散化为具体点位，并借助地理信息系统（Geographic Information System，GIS）工具进行微调优化。结合道路路网、人口统计信息等本地实际条件，本研究提出四步调整策略，以生成可直接落地的接驳公交服务实施方案。数值仿真结果表明，最终设计方案可使系统总成本至少降低3.5%。本研究阐明了轨道交通设计领域的前沿理论如何应用于实际工程，并凸显了理论研究与实践应用之间的紧密关联。