THE CONCEPT OF FUNCTIONAL DENSITY IN URBAN PLANNING: STRUCTURE, INDICATORS, AND TRANSFORMATION SCENARIOS

The article explores the concept of functional density as a multidimensional indicator of the spatial organization of the urban environment, which encompasses morphological, functional, social, and infrastructural characteristics. The urgency of the topic is driven by the need to reconsider urban planning principles under the conditions of full-scale war, large-scale internal displacement, and the growing pressure on municipal infrastructure, particularly in the rapidly expanding cities of western Ukraine. The core problem lies in the lack of a unified methodology for measuring functional density and its insufficient integration into urban policies. A review of recent studies (Gehl, 2010; OECD, 2012; UN-Habitat, 2020) highlights increasing international attention to functional density as a driver of mobility, accessibility, and efficient land use. In Ukraine, this theme is developed in the research of S.I. Konyk and in applied initiatives like Urban Vision Lutsk (2024), which demonstrate the potential of functional profiling and spatial diagnostics. The aim of the article is to conceptualize functional density as a complex and integrative category, clarify its internal structure and measurable indicators, and identify its practical potential in spatial planning. The article focuses on four main dimensions: morphological (e.g., FAR, GSI), functional (functional mix, entropy), social (usage rhythm, service access), and infrastructural (network connectivity, mobility integration). Based on these, a typology of urban fragments is proposed, ranging from mono-functional peripheries to polyfunctional urban cores. Several transformation scenarios are considered—decompression, diversification, revitalization, and repurposing—alongside prospects for digital monitoring using GIS-based tools. The conclusions summarize the conceptual and methodological basis for analyzing functional density and outline directions for further research, particularly concerning post-war urban recovery, spatial rebalancing, and the institutional implementation of functional indicators.