Analysis the change of vibration responses for tall building structure under earthquake

Abstract

Along with the continuous progress of science and technology, the tall buildings in the world in general and in Vietnam in particular have been developing with the progress of height as well as complexity. As the height of the building increases, the complexity of the design also increases, especially the work of determining the building’s responses to actions such as earthquakes. Therefore, the vibration analysis of tall building structures under the earthquakes is an issue that needs attention and is necessary for research. In this study, the vibration characteristics of a real tall building are analyzed for free vibration and vibration caused by earthquakes. Firstly, the reinforced concrete tall building structure is simulated by the finite element method using specialized structural analysis software SAP2000. Then, the vibration responses (acceleration, natural frequency, mode shape) of the structure are analyzed. The acceleration responses are extracted from survey points along the building height. The frequency domain decomposition (FDD) method is employed to determine the vibration characteristics (natural frequency, mode shape) of the building by analyzing the acceleration data caused by earthquake. Finally, the vibration characteristics when the structure is subjected to earthquake are compared and evaluated in accordance with the results of free vibration analysis.