Study on the influence of voids on high-rise building on the wind environment

Li, Yangluxi; Chen, Lei

Wind damage in cities was usually caused by tall buildings because they often produced unpredicted or dangerous wind environment at the pedestrian level (Melbourne and Joubert 1971; Murakami et al. 1986 ). In spite of uncomfortable environment for pedestrian was usually attributed to the high wind velocity, wind-related environmental problems have transmitted from dangerous high wind velocity to disadvantageous low wind speeds (Chetwittayachan et al. 2002; Goyal and Sidhartha 2002; Tsang et al. 2012) . For example, Hong Kong's dense high-rise buildings and large platform structures had greatly reduced wind penetration, resulting in poor low wind speeds at the pedestrian level (Chetwittayachan et al. 2009; Goyal and Sidhartha 2012) . Extensive stagnant air promoted airborne pathogens, such as the SARS virus (Severe Acute Respiratory Syndrome), posing a threat to public health (Yu et al. 2004 ). In addition, the average wind speed was lower than the minimum average wind speed of 1.5 m/s required by Hong Kong's air circulation assessment, which will cause outdoor heat discomfort to pedestrians, especially during the hot summer months (Ng 2009) Therefore, people have increasingly focused on low airflow velocity districts around high-rise buildings, which may result in poor outdoor air quality. Research done so far with respect to airflow condition around the construction has been performed for more than 50 years. Blocken and Carmelie (2004) reviewed a lot of researches in terms of outdoor human comfort degree studies since from the 1960s and found studies about airflow environment at pedestrian level mainly concentrated on the poor surroundings caused by strong wind flow around high-rise buildings (Wiren 1975; Stathopoulos and Storms 1986; Uematsu et al. 1992; Jamieson et al. 1992 ;