基于出行链的城际铁路站点选址双层目标模型

A Bi-Level Objective Based on TripTrain for Inter-City Rail Stations

摘要:

为解决因站点布局不合理导致投资成本高、旅客出行不便、客流吸引效果差的城际铁路选址问题，以出行链为基础，根据城市路网形态细化出行广义费用，弥补了既往研究中忽略或简化市内出行广义费用的不足.运用Logit模型，计算出行链中不同交通方式组合的分担率.分别以城际铁路运营收入最大为上层目标，在出行链中旅客广义费用之和最小为下层目标，建立城际铁路站点选址双层目标模型，利用改进离散粒子群算法进行求解.以广珠城际线为例，对模型及算法进行应用，并分析相关参数的敏感性，结果表明：模型的Pareto最优解体现了实现双层目标的矛盾关系，以此为基础结合不同设站需求实现两者的均衡，模型可为城际铁路站点选址提供更合理的决策支持.

关键词:城际铁路;站点选址;出行链;双层目标模型;粒子群算法

Abstract:

Unreasonable site location selection of intercity railway stations usually results in high investment and poor attraction of passenger volume. For that the previous studies neglected or simplified the calculation of broadsense travel utility in a city (a part of tripchain utility), the paper proposes an innovative model on the basis of the tripchain characteristics and employs the logit model to estimate the probabilities of various travel modes along the trip chain. A bi-level objective function based on the trip chain is developed to maximize the incomes of intercity rail operations (the upper level) and minimize the costs of passenger travels (the lower level). The improved particle swarm algorithm is utilized to find the optimum solutions. The results of the case study on the railway site location selections in Zhuhai City indicate that the Pareto optimum of model suggests the contradictive relationship between the objective functions at the upper and the lower levels, which is essential to identify the optimum tradeoff among the various demands of the rail stations. The model serves to provide a reasonable decisionmaking procedure for the planning of the railway site location selections in the future.

Key words:inter-city rail; site location selection; trip-chain;bi-level objective model; particle swarm algorithm