Two-Dimensional Numerical Analyses of Earthquake Response of Earthdam
| Autor: | Jun-Nan Li, 李俊男 |
|---|---|
| Rok vydání: | 2005 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 93 This study used FLAC5.0 to analyze the dynamic response of Li-yu-tan earthdam subjected to the 1999 Chi-Chi earthquake (ML=7.3) in Taiwan. The dam is 96m high. Seepage analysis was performed considering a 60-meter water level which was the level while the earthquake struck. After the seepage analysis, the initial stress state of the dam before applying the earthquake was obtained by computation for static equilibrium. Because the up-down shaking of Chi Chi earthquake is notable, both the horizontal and up-down monitored acceleration time histories were input to the base of the dam for 50 seconds in the dynamic analyses. The frequencies of accelerations were filtered to be under 5 Hz before input. The FLAC built-in “Sigmoidal 4” linear equivalent dynamic model and Mohr-Coulomb soil model were simultaneously adopted with a 5% Rayleigh damping assignment. The numerical results are close to the acceleration/ displacement time histories monitored at the top of the dam. Permanent displacements at the top, upstream and downstream shells were also evaluated with the theodolite data. The comparisons are satisfied with reasonable ranges of differences. This research use the analysis results of Li-yu-tan Dam subjected to Chi-Chi earthquake as the baseline case for parametric study. It is found that the major factors influence the displacement and acceleration of dam including shear modulus G, constitutive model, water level, damping and the way applying earthquake acceleration. This study found that bi-axial (horizontal and vertical) input of acceleration is better than only single (horizontal) input of acceleration. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
| Externí odkaz: |
|