Probabilistic-based analysis of concrete gravity dams under synthetic ground motion excitation

This research investigates seismic analysis of concrete gravity dams subjected to synthetic ground motions in the uncertainty Eamework. Many stud.ies focused on only epistemic randonmess due to material properties of concrete gravity dams and the impact of aleatory randomness due to seismic excitation is neglected. The latter source of randomness can significantly affect the results of analyses. Hence, in the current study, uncertainty due to earthquake excitation is tackled using synthetic ground motions. Inaddition, probabilistic characteristics of materials are taken into account along with artificial ground motion to form the seismic probabilistic-based analysis. The dam-reservoir-foundation model is employed for the uncertainty analysis. Generation of synthetic accelerogram utilized in this study is an iterative process based on Fourier transformation and target spectrum as well as baseline and PGA correction. Latin Hypercube sampling is utilized for the purpose of reliability analysis because of its lower computational cost relative to crude Monte Carlo Simulation for the same accuracy. The utmost goal of this research is to determine the exceedance probabilities of defined limit-state ftmctions as well as the probability distribution fimction of the dam’s response.

Keywords:

Concrete gravity dam , seismic analysis , reliability , synthetic ground motion , exceedance probability