A Traffic Assignment Approach for Multi-Modal Transportation Networks Considering Capacity Constraints and Route Correlations

Jia-Xiang Zhu,Qing-Yu Luo,Xue Bing,Jin-Ling Yang,Xin-Yu Guan

doi:10.1109/access.2020.3019301

Abstract

A multi-modal urban transportation network provides travelers with diversified and convenient travel options. The study of multi-modal traffic assignment encounters great challenges from the common-line problem, route correlation, and the variability of travel tools. This article starts with the construction of super-networks to solve the common-line problem of multi-modal system. From the dimensions of time, fee, comfort, and transfer penalty, a multi-modal generalized travel cost function is proposed to reflect the impact of travel mode and transfer on route choice. Based on C-logit model, considering multi-modal capacity constraint and route correlation, a nonlinear programming model equivalent to the multi-modal stochastic user equilibrium is set up. The corresponding solving algorithm is designed by combining the augmented Lagrangian multiplier method and the successive weight average algorithm. Finally, the effectiveness of the proposed model and algorithms is verified through a numerical example, and the traffic assignment approach is applied in some typical scenarios. The multi-modal transportation network equilibrium approach proposed in this article takes into account the capacity constraints of different travel modes and solves the path overlapping problem in combined modes. It provides a basis and tool to formulate the traffic management strategy for public transport and combined mode trips.

Highlights

With the continuous development of transportation, urban travel has changed from a single mode to a diversified and complex multi-modal mode
Based on the Wardrop’s first principle, we propose the SUE principle in multi-modal assignment: all travelers will make mode and route choice with the lowest generalized travel cost
SOLUTION ALGORITHM The augmented Lagrangian multiplier (ALM) is adopted to solve the traffic assignment problem with capacity constraints, which can be viewed as an extension to the penalty method

Summary

INTRODUCTION

With the continuous development of transportation, urban travel has changed from a single mode to a diversified and complex multi-modal mode. In order to study the traveler’s choice behavior of intercity buses and trains in the multi-modal urban economic circle transportation network, Li et al established a combined model of mode split and traffic assignment [19]. Si et al studied the UE model in multi-modal networks, based on the principle of minimum generalized travel cost in the mode split stage, and the principle of shortest travel time in the route choice stage, and constructed an equivalent variational inequality (VI) function to solve it [24]. 1) For the multi-modal traffic assignment containing combined mode trips, dividing travel choice into multiple stages is too complex. This kind of division is not appropriate for large-scale road network, and will weaken the relationships among the stages in travel choice. (1) There are no circle and repeated link in the effective path

MULTI-MODAL GENERALIZED TRAVEL COST

Generalized Travel Cost Function of Combined Public Transit Mode

MULTI-MODAL STOCHASTIC USER EQUILIBRIUM PRINCIPLE ANALYSIS

SOLUTION ALGORITHM

Findings

CONCLUSION