Model formulation and calibration procedure for integrated multi-modal activity routing and network assignment models

Abstract

In this paper, a novel transport planning model system (TPMS) is formulated built on the concepts of network, multi-modality, integrity and instant calibration. In the proposed formulation, activity-travel pattern (ATP) choice elements including the choices of activity, activity sequence, mode, departure time, and parking location, are all unified into a time-dependent ATPs generator. The proposed model accounts for the dynamicity of the network, including time-of-day and congestion effects in a joint structure for transport supply and demand. Moreover, the proposed TPMS explicitly formulates an operating capacitated public transport system. To allow visiting locations multiple times and to alleviate the complexity of the proposed model, a novel multi-visit vehicle routing problem is proposed which does not enumerate the node and link visits. In order to calibrate the model based on the major travel attributes of the travel survey data, a set of splitting ratios are introduced to distribute trips on the network. The model uses the splitting ratios to integrate the ATPs generator and the traffic assignment (TA) model in a unified TPMS structure. The effectiveness of the proposed structure is demonstrated through numerical examples provided.