Modelling behavioural responses to infrastructure development in megacity regions

Source abstract

Understanding how large-scale transport infrastructure shapes mobility patterns and the spatial structure is essential for assessing the impacts of urban development and policy. However, it is a challenging task given the dynamic nature of urban processes, and it is even more so in a megacity context. This study proposes a simulation-based framework that combines travel behaviour modelling with functional zone delineation to assess the impacts of infrastructure development. The framework builds on a two-step spatial interaction model in which localised distance-decay parameters are estimated for socioeconomically differentiated area clusters. Predicted flows from the spatial interaction model, incorporating projected population and updated travel time, are fed into a regionalisation algorithm that delineates urban functional zones. We illustrated the framework through a case study of the Shenzhen–Dongguan–Huizhou–Zhongshan region, simulating the opening of the Shenzhen–Zhongshan Bridge in the China Bay Area. Results demonstrated substantial reductions in cross-estuary travel impedance and a reconfiguration of functional boundaries, with parts of Zhongshan becoming functionally integrated into Shenzhen. However, average travel distances increase as greater accessibility enables longer-distance commuting, which is a counterintuitive yet insightful observation. Overall, the proposed framework has been shown to be a scalable instrument for linking behavioural heterogeneity, infrastructure modifications, and the emergent urban spatial structure within rapidly integrating mega-city regions.