Wind tunnel study of pedestrian level wind environment around tall buildings: Effects of building dimensions, separation and podium

It is well known that high-rise buildings affect the surrounding pedestrian level wind environment. In recent years, awareness and concern has increased about the creation of low wind speed areas around tall buildings which may lead to poor out-door air ventilation. In addition, new building developments are often not restricted to a single building, but comprise a row of buildings, which may have complex plan-forms, and some integrating an extensive podium. This paper aims at providing a fundamental understanding of wind-structure interactions that govern the effects of building dimensions and separations, a row of buildings and podium on the pedestrian level wind environment, for both weak and strong wind conditions, by a series of parametric wind tunnel studies. The study area covered an extensive area which covered up to 400 m downstream of the test buildings. The results show that a single wider building created adverse effects on the natural air ventilation at pedestrian level around the building while a taller building improved the near-field air ventilation conditions. In the studies of building separation effects, the results show an adverse effect on natural air ventilation at pedestrian level when the building separations are less than half the building width. Inclusion of a podium was also found to adversely affect the air movement around buildings. (C) 2011 Elsevier Ltd. All rights reserved.