Wind interference effects of high-rise building on low-rise building with flat roof

Abstract Wind pressure measurements were conducted in a wind tunnel to investigate interference effects of a high-rise building on a low-rise building with a flat roof. The influences of the building spacing ratio, building height ratio and wind direction are examined. The results show that positive pressures are observed on the roof of the low-rise building when it is located in front of the high-rise building with small spacing. Increasing the height of the high-rise building or decreasing the spacing induces an increase in positive pressures. The critical condition of the sign change of wind pressures on the roof is presented. Significant amplification of suction is observed when the low-rise building is right behind the high-rise building with small spacing and large height ratio. Increasing the height of the high-rise building greatly amplifies the suction on the whole roof of the low-rise building. The mean lift coefficient on the roof is about 2.5 times that on an isolated low-rise building roof when the spacing ratio is small and the height ratio is large. The maximum interference factors of the most unfavorable minimum and maximum coefficients in the roof area near the high-rise building are larger than 1.5 and 3.5, respectively.