Journal of Structural and Construction Engineering (Mar 2020)
Evaluation of seismic responses of an arch dam under non-uniform ground motion using random vibration
Abstract
To investigate the seismic responses of dams due to ground non uniform displacements, the records of earthquake displacements are required. Such data is seldom recorded during a specific earthquake and in the most cases the recorded data in not sufficient for non-uniform analysis of a dam. In this study non uniform accelerations are generated using Kanai-Tajimi spectrum with considering wave passage, incoherent effects and coherence spectrum model. A 3-d finite element model of dam-foundation of Karun 4 arch dam as the highest dam in Iran is modeled. The model is analyzed under uniform and non-uniform generated accelerations and its responses are investigated. The results show that, non-uniform excitation leads to differences in seismic response than uniform excitation on dam. It is indicated that considering non-uniform excitation in seismic analysis increases the stresses and displacements on the dam body. To investigate the seismic responses of dams due to ground non uniform displacements, the records of earthquake displacements are required. Such data is seldom recorded during a specific earthquake and in the most cases the recorded data in not sufficient for non-uniform analysis of a dam. In this study non uniform accelerations are generated using Kanai-Tajimi spectrum with considering wave passage, incoherent effects and coherence spectrum model. A 3-d finite element model of dam-foundation of Karun 4 arch dam as the highest dam in Iran is modeled. The model is analyzed under uniform and non-uniform generated accelerations and its responses are investigated. The results show that, non-uniform excitation leads to differences in seismic response than uniform excitation on dam. It is indicated that considering non-uniform excitation in seismic analysis increases the stresses and displacements on the dam body.
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