建筑外文翻译--超高层建筑结构横向风荷载效应(编辑修改稿)内容摘要:

n and aerodynamic force are difficult to obtain using this kind of method. High frequency force balance technique. Compared with the pressure measuring technique, high frequency force balance technique has its unique advantage for obtaining total aerodynamic forces. The test and data analysis procedures are both very simple。 hence, this technique is monly used for selection studies on architectural appearance in the initial design stage of supertall buildings and structures. Currently, this technique is widely used for total wind loads acting on supertall buildings and structures, and for dynamic response putation as well. The high frequency force balance technique has been gradually developed since the 1970s. Cermak et al. were the first to use this technique for building model measurement. They initially pointed out that the balancemodel system should have a higher inherent frequency than the concerned frequency of wind forces. The fiveponent balance developed by Tschanz and Davenport marked the maturity of balance facility. Kareem conducted an experimental study on acrosswind aerodynamic forces on tall buildings with various section shapes in urban and suburban wind co research showed that for the buildings with , uncertainties of wind and structural parameters have small effects on PSD of the acrosswind aerodynamic force, and the correlation between the alongwind aerodynamic force and the acrosswind aerodynamic force or the torsion moment is negligible, but there is a strong correlation between the acrosswind aerodynamic force and the torsion moment. This conclusion is important for the development of threedimensional refined wind load model. Particularly, Gu and Quan and Quan et al. made detailed studies on the effects of the side ratio of a rectangular building, crosssection shape of a building, aspect ratio of a building, and wind field condition on the PSD of the acrosswind aerodynamic force of tall buildings using a fiveponent balance. In fact, based on a large number of wind tunnel test results, formulas for acrosswind aerodynamic force coefficients of the typically tall buildings have been derived by us and other researchers, some of which are listed in Table 1. In addition, in Table 1, the formula derived by Gu and Quan has already been adopted in related design codes in China. Acrosswind aerodynamic damping In 1978, Kareem performed an investigation on acrosswind dynamic responses of tall buildings based on both of the aero elastic model technique and the wind pressure integration method. He found out that the acrosswind dynamic responses calculated with the acrosswind aerodynamic forces obtained from the wind pressure tests at a certain test wind velocity range were always smaller than those of the aero elastic model of the same building model. This important result made researchers realize the existence of acrosswind negative aerodynamic damping. Subsequently, researchers carried out numerous studies on the problem and developed effective methods for identifying aerodynamic damping. The first kind of method obtains aerodynamic damping by paring the dynamic responses puted based on the aerodynamic forces from rigid building model tests and those from aero elastic model tests. The second one separates aerodynamic damping force from the total aerodynamic force measured from aero elastic building models or forced vibration building models. The third kind employs identification methods for extracting aerodynamic damping from random responses of aero elastic models. Moreover, researchers realized the effect law of factors, including structural shape, structural dynamic parameters, wind conditions, and so on, on aerodynamic damping, Isyumov et al. were the first researchers to propose a method for aerodynamic damping through paring responses from a rigid building model test using HFFB technique with those of an aero elastic model of the same building. Cheng et al. adopted the method to study acrosswind responses and aerodynamic damping of tall square buildings and proposed an aerodynamic damping formula. Steckley initially developed a set of forced vibration devices for measuring total aerodynamic forces, including aerodynamic damping force and aerodynamic force. He measured the base bending moment of a tall building model, which was vibrated by a specially designed device. The aerodynamic force related to structure motion was separated from the total aerodynamic force, and then it was deposed into aerodynamic stiff force and aerodynamic damping force to obtain aerodynamic damping. Vickery and Steckley propo。
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