Determination of the alongwind dynamic response of the CAARC standard tall building

Abstract

Usually the structural behavior under wind action is evaluated by the Gust Factor Technique (GFT) which provides equivalent static forces acting on the structure. However, it is not possible to develop a more detailed dynamic analysis. Frequency domain analysis provides aclear description of the dynamic aspects involved, being this methodology widely used in research. Time domain analysis allows a detailed study of the phenomenon, evenunder a non-linear structural behavior. However, the analytical methods used for determining the wind action structural response generally lead to un-reliable results when applied to tall structures with unconventional geometries or structural surrounding. In these situations, wind tunnel tests are an accurate and robust tool to study the dynamic behavior of structures.In this work, a simplified numerical procedure and an experimental methodology for the determination of thedynamic longitudinal response of high structures under the atmospheric boundary layer wind action is implemented and discussed. The simplified numerical approach consists in simulating velocity time series, which define the wind velocity field and are subsequently transformed into nodal forces by a quasi-static assessment model. Longitudinal dynamic response of the structure in the time domain is obtained by the use of the Finite Element Method (FEM). Wind tunnel experimental evaluation was performed with the aid of a base-pivoted rigid model balance and the longitudinal fluctuating response was measured. In order to compare these different approaches, both procedures were applied to the determination of the longitudinal dynamic response of the CAARC Standard Tall Building.