Study On The Law Of Interference Effect Between High-rise Buildings On Wind Induced Pressure And Acceleration

High-rise buildings have witnessed a large increase in numbers and intensities due to rapid urbanization in recent year.The interference effects between buildings have become more and more critical.Correct evaluatio n of the interference effects under wind loads is of great importance.The existing research on this issue is not comprehensive and systematic.In reality,the phenomenon that the facade of structure is damaged under the strong wind loading can be found everywhere.It shows that the distribution characteristics of peak wind pressures under interference are not well understood.The interference effect of single parameter variation on the interference building is quite limited.As a result,the objective of this study is to investigate the interference effects on the wind pressure and the peak acceleration induced by interference buildings with different width and thickness ratios.As the static effect is affected by the mean wind pressure,the interference effect on it under different working conditions is studied firstly.The variations of the mean wind pressure under interference are analyzed by defining three different interference factors,SIF,FIF and IF.The SIF is used to calculate the distribution of the interference effect within the target area,and determine the representative location of the interference effect.The FIF is used to calculate the variation of the interference effect along the building height,and determine the representative layer on the principal building.The IF value of each pressure tap is calculated to analyze how the wind force changes on the selected representative floor.The contour map of SIF and the correlation formula of SIF are obtained.The formula of SIF,FIF and IF are proposed under the effect of the interference building in different width ratios and thickness ratios.Besides,the interference effects of thickness ratios and width ratios of the interference building are summarized.Excessive local peak pressure is the main reason for the damage of envelope structure,so the interference effect of peak pressure and wind pressure power spectrum under different working conditions is also studied in detail in this paper.The distribution of PIF(local peak pressure interference factor)in the studied area is investigated.According to it,the variations,local peak pressure and wind pressure power spectrum changing with their tandem or parallel spacing,are studied.At the same time,the representative location is confirmed.The interference effects of width ratios and thickness ratios on local peak pressure and wind pressure power spectrum are analyzed.The results showed that the windward surface of the principal building in tandem arrangement mainly shows the amplification effect.The augmentation is concentrated at the side edge and the upper edge,whereas the maximum IF=2.7,and the shielding effect located at the middle part.The right side of the principal building in parallel arrangement mainly showed the amplification effect concentrated at downwind part,where the maximum IF=1.3,and the shielding effect is at upwind part.The variations of local peak pressure under the effect of interference building in different spacing ratios,width ratios and thickness ratios are summarized.The change of flow field around principal building is preliminarily judged by observing the wind pressure power spectrum.Finally,the vulnerable parts of the principal building are summed.The building's top peak acceleration is a generally accepted index to measure the comfort of the building at present.Therefore,this paper also studies the interference effect of the peak acceleration at the top of the principal building in the downwind,crosswind and torsional directions.In this report,the IF(acceleration interference factor)contours of the top peak acceleration in the three directions under different working conditions are obtained.On the basis of this,the variations of the peak acceleration influenced by the change of tandem spacing and parallel spacing are analyzed.Besides,the maximum IF and its corresponding coordinates under different width ratios or thickness ratios are extracted and summarized.It is found that the maximum peak acceleration of the downwind increased by 53%,the maximum of crosswind increased by 33%,and the maximum of torsion increased by 35%.The distribution of the interference factor on the downwind and the crosswind is almost unchanged when the interference building thickness is less than that of the principal building.