Wind-induced Interference Effects Of A Tall Building On A Low-rise Building With Flat Roof

With the development of economy and city construction in China,many tall buildings are built as redevelopments in old urban areas.There are a large number of cases where tall buildings are erected around a group of low-rise buildings,which changes wind loads on low rise buildings greatly.At present,less studies have been conducted on the wind-induced interference effects between high-rise buildings with low-rise buildings,this paper investigates the interference effects of a downstream high-rise building on the low-rise building through wind tunnel tests.At first,the distributions of mean wind pressure coefficients,mean pressure coefficients of roof zones and the average force coefficient of three directions in different wind directions are discussed.Then,an interference building with different height ratios is located of the downstream of the low-rise building.The interference mechanism is investigated on wind pressure of the low-rise building and the interference building by changing the height ratio and distance between the two buildings.The results indicate that the wind pressure of low-rise building is sensitive to the two parameters.The boundary condition and amplitude of positive pressure of roof are directly related to the distance and the height of tall building.When the distance is relatively small and the height ratio is relatively high,positive pressure appears on the roof of low-rise building.However,as the distance increases or the height ratio diminishes,the positive wind pressure disappears soon.Next,a research on the interference factors of the roof lift force coefficients,the drag force coefficients along the wind,the lift force coefficients cross the wind,and the mean pressure coefficients of roof zonal area is discussed for different wind directions,different height ratios and different distances between the downstream building and the low-rise building.A critical height ratio when the positive pressure appears and becomes stable on the roof is identified.Moreover,the dependence of positive pressure area on the distance,building height and wind direction is studied.