Evaluating the Morphological and Functional Centrality: An Integrated Approach To Spatial Structure

Abstract A comprehensive understanding of urban spatial form and functionality is essential for developing effective strategies and anticipating the impacts of planning decisions. Despite the growing academic interest in functional approaches, urban centers in planning practice are still predominantly defined by morphological attributes. This conceptual limitation is particularly evident in developing countries, where the implementation of polycentric development strategies requires a more integrated, multidimensional framework that incorporates both functional and morphological centrality. This study introduces a comprehensive framework for empirically assessing urban spatial structures by integrating morphological and functional dimensions through GIS-based spatial and temporal analysis. The primary objective is to examine polycentric urban patterns from the perspectives of static urban form and dynamic urban flows and to develop a composite Integrated Centrality Index that unifies these two dimensions. Using Ankara as a case study, the findings reveal significant spatial mismatches between morphological and functional centrality. While population density and the provision of basic services shape morphological centrality, they are insufficient predictors of functional performance. In contrast, areas offering specialized services and land use diversity demonstrate higher levels of human mobility and functional centrality. Furthermore, the study highlights that topo-geometric street features correlate strongly with vehicular traffic, whereas metric attributes, particularly betweenness index, are associated with public transport travel. By linking spatial form with functional flows, this research offers a comprehensive approach for understanding urban centrality. The results provide critical insights for planners and policymakers, underscoring the need for mobility-oriented, functionally diverse strategies that move beyond morphology-driven urban planning paradigms.