Multilevel Multimodal Network Modelling: The Spatial Impacts of The Public Transport on Urban Systems

Transportation plays an essential role in supporting people and freight movement in cities and regions. The physical infrastructure of the transport network is usually embedded as a part of urban structure to link spaces and cover a significant amount of ground. However, accessibility studies, especially the space syntax theory and measurements, mainly focus on modelling and analysing the street network without concerning the public transport network. Although space syntax methodology has been proved to successfully examine the configurational urban form and the related effects on the pedestrian and vehicular flow within the street network, the effect of rail-based public transport is still missing in most space syntax studies. Therefore, this study applied a synthetic methodology to examine the multilevel multimodal network by combining railways and streets into a united network model. An Integrated Urban Model (IUM) has been developed to uncover the network and land use accessibility in cities and regions. This study further explored the distance cost in Depthmap by adopting time-cost distance for every segment based on the speed of transport modes for multimodal travelling. The results indicated that the multilevel multimodal model could provide a new vision of the network centrality. The study demonstrated that the concept of time-cost distance, along with metric distance and angular cost, could be a new approach for measuring the accessibility of the multilevel network in cities and regions