Sustainability, Vol. 9, Pages 1656: Influence of the Ground Greening Configuration on the Outdoor Thermal Environment in Residential Areas under Different Underground Space Overburden Thicknesses (Sustainability)

In the underground space development of residential areas, outdoor thermal environments at the pedestrian level greatly depend on the ground greening configuration, which is in turn affected by the overburden thickness of the underground space (OTUS). However, few studies have considered the effects of OTUS on the ground greening configuration and the further effects of the ground greening configuration on the outdoor thermal environment. This study aimed to provide insights into the design of OTUS for improving outdoor thermal environments. Two residential areas with row and enclosed layouts in Nanjing, China, were numerically studied using the computational fluid dynamics (CFD) simulation software ENVI-met. Outdoor thermal environments in the two residential areas, which had the same greening coverage rate, were simulated under different OTUSs and ground green configurations. The results indicate that to create a comfortable outdoor thermal environment, the OTUS should be designed to satisfy the requirement for planting small trees. If this requirement cannot be adequately satisfied, individuals can also set up tree wells or add soil on top of underground structures to plant small trees, and establish an OTUS that can satisfy the requirement of planting large shrubs in other areas.