Characteristics Of Wind Loads On A Super High-rise Buildings Controled By Upper-surface Suction

As a result of the extensive application of high-strength light-weight materials andemergence of new structure systems in construction, the height of modern urbanstructures is getting higher, and the damping ratio is getting smaller. Therefore, it bringsa new challenge to the wind-resistance design for super high-rise buildings. Takingaerodynamic measures to reduce the wind loads on and wind-induced responses ofsuper high-rise buildings has been proven to be an effective means to improve theirwind-resistance performance. Introducing the suction control method, which was widelyused in domains of the aerospace and fluid machinery, into the wind-resistance designfor super high-rise buildings is a rising topic in recent years. Although some researchwork has been carried out via the computational fluid dynamics method, moresystemetic and in-depth investigations should be conducted using the wind tunnel testsand more accurate numerical simulation methods.Under the circumstances, many previous research achievements are summarized,and characteristics of the mean and fluctuating wind loads on a super high-rise building,which is controlled by air suction at the upper surface, are investigated using both thewind tunnel test and CFD numerical simulation methods. The main contents in thedissertation are shown as followings:1. Based on some existing experimental techniques on the suction control, asuction control system (including a draught fan, two flowmeters, pipes and two vavles)is designed for further experimental investigations.2. Wind tunnel test of the rigid model of a super high-rise building, which iscontrolled by upper-surface suction, is accomplished. Based on the wind tunnel test results,effects of the orifice geometrical parameters and the suction flux parameters oncharacteristics of the mean and fluctuating wind loads on the model under differentwind directions are analyzed, and coefficients of wind loads reduction are calculated toquantify the suction controlled effects.3. The characteristics of wind loads on the super high-rise building under thesuction control are numerical investigated, using both the Reynolds-averaged Navier-Stokes (RANS) method and the large eddy simulation (LES) method. Compared withthe results from wind tunnel test, the numerical simulation results exhibit reasonableaccuracy. Therefore, the reliability of the numerical simulation method is validated. Byshowing the detailed flowfields around the super high-rise building, the mechanism ofsuction control over the wind loads reduction is clarified.