Influence of intensity parameters of earthquake on response of reinforced concrete structures

Abstract

Earthquake is one of the most frightening and destructive phenomena of nature. The destructive capacity of an earthquake depends on various parameters. Without characterising earthquake time history data to the required intensity parameters, its effect on structures cannot be predicted. The influence of intensity parameter of earthquake on the destructive capacity of a structure is essential in the vibration control scenario also. In the present paper, three reinforced concrete (RC) framed structures with natural frequencies 4.688 Hz, 1.762 Hz, 1.661 Hz are used to investigate the influence between the intensity measures and the response. 20 ground motion time history data were selected with predominant frequency ranging from 1 Hz to 12.5 Hz. Some available intensity measures were used to characterise this data. 3D model of the structure was analysed in ETABSUL 13.1.3 software with diaphragm rigidity at floor level. Modal analysis was used to find the modes and corresponding time periods. Linear time history analysis was done for the three models for all the ground motion data. It is noted that four intensity parameters namely predominant frequency, Peak Ground Acceleration, Velocity Spectrum Intensity, Housner Intensity has an appreciable influence on the response.