What factors drive the vitality of rail transit station areas? An investigation of urban features in Tianjin, China

Rail transit station areas function as high-traffic nodes that merge mobility with commerce, services, and public life. However, existing research disproportionately emphasises traditional public spaces such as streets and parks, overlooking station areas as critical loci of activity. Using the GTWR model and hourly Baidu Heatmap data, this study investigates how urban characteristics shape vitality in Tianjin's rail station areas, capturing fine-scale spatiotemporal variations in human activity. Findings show that centrally located, commercially concentrated stations exhibit heightened vitality, typically following a bimodal daily rhythm. Variables such as public service density, floor area ratio, and bus route integration exert significant yet location-sensitive impacts. By combining spatiotemporal modelling with real-time population proxies, this research contributes an adaptable methodology and practical guidance for revitalising transit-adjacent urban areas. The findings provide practical insights to improve the vitality and efficiency of station-adjacent urban environments.