Abstract: Because of the dispersion of the time and space of its service objects, the general route planning of public transportation is the most difficult part of the public transportation system in big cities to plan. This paper analyzes the hierarchical functions and planning sequence of the public transport network in large- scale multi-center urban areas, and puts forward a method of building a continuum approximation model based on the lowest generalized cost of operators and users for the general line network. This method minimizes the generalized expected cost of bus operators and passengers per unit time by determining the optimal value of decision variables such as the total service distance of the general line of the regional network, the total number of stops, and the departure interval. Using the proposed, after the regional division of Beijing, the general line network was re-optimized. Based on the distribution of Beijing's road network and points of interest, the planned ideal network was checked, and a design that could be implemented was obtained. Compared with the current network, the optimized solution has been significantly improved in terms of cost control and passenger travel experience, reducing corporate operating costs by 5% and passenger travel time by 21%, achieving the goal of reducing costs and increasing efficiency.

Key words: urban traffic, transit systems design, continuum approximation, generalized cost, grid structure

摘要： 公交普线规划因服务对象时间、空间的分散性，是大城市公交系统中最难规划的部分。本 文分析了大规模多中心城市地区公交网络分层级功能及规划次序，重点针对普线网提出基于运 营商和用户广义成本最低的连续体近似法模型搭建方法。通过确定区域网络的普线总服务距 离，总停靠站数，以及发车间隔等决策变量的最佳值，使公交运营企业和乘客在单位时间内的广 义预期成本最小化。利用本文提出的方法，对北京市进行区域划分，重新优化普线网，并基于北 京市路网和兴趣点分布，校核规划的理想网络，得到能够实施的设计网络。相比现状网络，优化 后的方案在成本控制和乘客出行体验方面都得到明显提升，分别减少企业运营成本5%，减少乘 客出行时间21%，达到了降本增效的目标。

关键词: 城市交通, 公交系统规划, 连续体近似法, 广义成本, 网格布局