Does Transportation Infrastructure Alleviate Urbanization Imbalance: The Perspective of Urban Spatial Structure

The unbalanced pattern of population urbanization lagging behind land urbanization constrains the sustainable development of cities. Enhancing transportation infrastructure emerges as a viable strategy to mitigate urbanization imbalance. This study investigates how HSR and subway can address urbanization imbalance in Chinese cities, which have witnessed the most intensive urbanization and transportation infrastructure development in the 21st century. Employing panel data of 279 cities from 2006 to 2021 and utilizing a DID methodology, the empirical analysis reveals that HSR operation significantly promotes population inflow and enhances land use efficiency, effectively mitigating urbanization imbalance. The mechanism stems from HSR‐induced polycentric spatial restructuring, which expands population agglomeration spaces. Critically, subway networks functionally integrate emerging subcenters with primary urban cores, creating synergistic effects with HSR to optimize urban spatial structures. However, peripheral cities, hampered by the lack of subway connectivity, fail to leverage HSR to alleviate urbanization imbalance. These findings underscore that multimodal transport systems are essential for enhancing cooperative accessibility and achieving urbanization rebalance.