Assessment of the influences of post-construction facilities on pedestrian-level wind environment: An experimental study in Changsha, China

With continuous urbanisation, an increasing number of post-construction facilities (such as high-rise buildings and green plants) have altered the original layout of the community. Which has resulted in deterioration of the wind environment. However, there is a deficiency of qualitative studies on the pedestrian-height wind environment that focus on the influence of post-construction facilities. The presents research takes Changsha universal time community as a case study. A wind tunnel test at a scale of 1:250 was performed to analyse the wind environment by considering the post-construction facilities. 81 sets of cases with different inflow patterns, wind directions, adjacent high-rise buildings, and plants were examined to reveal the flow field distribution characteristics. Furthermore, the exceedance probability method was introduced to assess the wind environment of the community in different cases. The results indicate that the index distribution coefficient of wind velocity and the turbulence intensity profile inside the practical community is significantly larger than the code values. A roughness distance of 800 m can generate highly effective mean wind profiles. However, it is unable to generate the desired turbulence profiles. Considering the post-construction facilities, high-rise buildings cause acceleration effects on the average wind velocity and the acceleration effects are inversely proportional to the distance of the post-construction facilities. Large, medium, and small trees cause deceleration effects of the average wind speed and improve the wind environment comfort quality of the community.