Experimental Study The Aerodynamic Damping Characteristics Of Rectangular Section High-rise Buildings In All Wind Directions

With the rapid development of science and technology and considering theneeds of the economical use of land in the city, high-rise building is being greatlyconstructed in our country. As the increase of the height of the high-rise building,accurate estimates of the wind-induced response of high-rise building is of primeimportance to structural design. The most important work is to accurate estimation ofwind load and damping when we accurate estimate of the wind-induced response.Aerodynamic damping is a part of the total structural damping, its value may bepositive or negative. Ignoring the influence of aerodynamic damping on wind-inducedresponse of high-rise building structure can lead to an unsafe design. At present, theobtain of aerodynamic damping mainly by the wind tunnel test. Based on the existedresults and theories, In this paper, the regular of aerodynamic damping with windattack angle and the reduction velocity of high-rise structures through axial directionis conducted by tunnel tests of aerodynamic elasticity model with rectangular sectionwhich its flakiness ratio is1:2. Around this goal, this article main work is as follows:(1)According to the test target, the design method of the single-DOFaeroelastic models and the wind tunnel test procedure are firstly introduced,and madea kind of1:2ratio SDOF aeroelatic models of the building.Then selected the class Blandscape wind field in China on "load code for the design of building structures",andtested in the high-speed section of HD-2wind tunnel lab in Hunan University.(2)This thesis mainly introduced the random decrease method. Thedevelopment and application of the random decrement method are briefly introduced,so that can we use this method to obtain the aerodynamic damping of high-risebuilding accurately.Then, studied the influential factors of the random decrementmethod, including the motivation, the trigger condition, sample size, given animportant reference to select parameters when use this method.(3)Through eliminating the polynomial trend of the original datas and digitalfiltering processing, first using the random decrement method to identified the totaldamping, then according to the structural damping changing with the amplitude, theangle of0°~90°direction aerodynamic damping of the high-rise building alongwith the reduction of wind speed change rule are given.At the end, a summary of the research are given and futre work on aerodynamic damping was briefly discussed.