Investigation Of Wind-induced Interference Effects On Tall Buildings

Since the development of economy and progress of science&technology and the increase of population, more and more dense-high-rise buildings have come to appear in modern cities. Because of interference effects from other nearby tall buildings, wind loads on buildings may be had biggish difference relative to that of isolated buildings, sometimes changed farther bigger than that of isolated structures.Based on the high frequency force balance technique, wind tunnel model test is used to investigate the wind-induced interference effects on tali buildings in this paper. The static, along-wind and across-wind dynamic interference effects from other nearby tall buildings of various shapes in 4 kinds of exposure categories carried out by using codes are studied . The results show that the static interference is mostly embodiment of curtain effects. However the dynamic interference embodies mostly effects of increase. Along with the increasing of exposure category exponents, the static and dynamic interference effects are reduced. This paper gives emphasis to investigating the differences of interference effects by nearby interfering builings of various shape sections. The tested maximum dynamic envelope interference factors (EIF) of the comer-cut buildings are found up to 4.41 and 3.69 in the along-wind and across-wind direction. The results also show that the downstream buildings can also significantly enhance the dynamic wind load on the upstream interfered building and the tested factors are found up to 1.95 and 2.96 in along-with and across-wind direction.In order to make experimental results simpler and sever for actual projects, this paper also investigates the relativity of the wind-induced interference effects on tall buildings of various shapes in different exposure categories. Results show good relativity among exposure categories and comer-cut sections interfering buildings with static and dynamic interference effects. Based on the recursive formularies summarized in this paper, we can calculate to the IF of other section-shapes interfering buildings in different exposure categories from the IF of the basic arrange.Besides analyzing, comparing, summarizing the experimental datas, the overturning moment spectra and vortex shedding spectra are used to analyze the interferefering mechanism. The results show that the higher vortex shedding frequency is induced by the corner-cut interfering building, its dynamic interference effect is found to be more significant than that of a square section interfering building.