Investigating residential noise distribution through urban section and profile analysis: a case study of Nanjing

Abstract As urbanization accelerates and population density rises, noise pollution increasingly undermines residents’ quality of life. While the link between noise distribution and urban morphology has been widely established, most studies focus on two-dimensional noise patterns and overlook its continuous three-dimensional variation. This study proposes a method that integrates urban section analysis with noise simulation. Taking typical residential forms in Nanjing as case studies, we treat profiles as core analytical units and incorporate noise simulation data from CadnaA to generate section-based maps that illustrate noise propagation paths and intensity variations. Based on a 50 threshold, high-noise and quiet areas are identified, and an area density index is introduced to enable quantitative comparison across residential morphologies. The results reveal that building form and layout significantly influence noise propagation and attenuation. Compact low-rise layouts foster stable quiet areas, whereas high-rise and wide-spaced layouts often create noise corridors that channel noise deeper into the site. Across cases, a consistent spatial pattern emerges: noise attenuates from the perimeter inward; the first building row provides substantial shielding; and noise troughs frequently occur at interfaces between buildings and open spaces. This section- based framework advances the analysis of coupling between urban morphology and acoustic environments and offers a rigorous basis for optimizing residential layouts and guiding urban acoustic environment management.