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碩士論文公告區 |
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| 年度： | 96 | |
| 姓名： | 梁正育(Cheng-Yu Liang) | |
| 論文題目(中)： | 土石壩幾何條件對其力學行為影響之研究 | |
| 論文題目(英)： | Effects of the Geometrical Parameters on the Mechanical Behaviors of Earth Dam | |
| 摘要(中)： | ||
| 本研究以有限差分為基礎之數值分析軟體FLAC 3D程式來進行寶山第二水庫築壩過程中壩體的受力行為、蓄水後壩體滲流與力學行為以及在921地震加速度下之動態行為的模擬以驗證分析方法之正確性。然後改變土石壩之壩長與壩高的比值、心牆底寬與壩高的比值，探討這些參數對土石壩體力學性質之影響。在檢核分析中，模擬寶二水庫的分析結果與現場監測值和2D模擬分析結果相當吻合，因此本研究的分析方法有其正確性，而且寶二水庫因壩體長度夠長，因此以平面應變的2D模擬分析即可得到3D模擬的分析結果。由於寶山第二水庫並未遭遇強震之侵害，本研究以921集集地震加速度施加在壩底，以了解其在破壞型地震下之動態反應，由本研究發現壩體除下游殼層之表面會發生破壞以外，壩頂之沈陷量與壩體皆屬於安全範圍。在壩體幾何尺寸影響評估中，當壩長與壩高比值≧4，可忽略3D效應。自然振動頻率隨著壩長的增加而降低，其共振頻率主要約在3Hz。當心牆底寬與壩高比值≧0.9，對沉陷量變化影響不大，蓄水後的自然頻率高於蓄水前的頻率，當壩心的比例增加時，其頻率也隨著降低。當壩長與壩高比值等於6和心牆底寬與壩高比值等於0.9時，蓄水後的自然頻率最高，其次為蓄水前的自然頻率，接著為地震後的自然頻率，最小的是集集地震下壩體的卓越頻率，心層的自然頻率較上下游殼層的自然頻率為低。 | ||
| 摘要(英)： | ||
| This research used FLA3D, a numerical analysis software based on the finite difference method, to analyze the mechanical behaviors of Pao- Shan in construction stage, and 921 Chi-Chi earthquake. These numerical results were compared with monitoring identify the rational of analysis method in this study. From the numerical results, they are close to the monitoring results and plane strain (2D) results. Therefore, the numerical analysis is rational in this study, and it can be so long enough that the 3D results are close to 2D results. And then the mechanical behaviors of earth dam were discussed for various ratio of length and weight of dam and ratio of width and height of core. In order to identify the safety of the second reservoir of Pao-Shan under the strong earthquake, 921 Chi-Chi acceleration-time history was added on the base of the dam. The results show it is in safety state except for the crust surface on the downstream of the dam. In the influence evaluation of geometrical parameters, as the ratio of length and height≧4, the 3D effect is able to neglect. Natural vibration frequency will reduce with the length increasing of the dam and the frequency is mainly about 3Hz. As the ratio of core base-width and height≧0.9, it is less influential on the deformation. After seepage stage,the natural frequency is higher than that of before seepage stage. As the ratio of core increase, the frequency will reduce. As the ratio of the length and height is equal to 6, and the ratio of the core base-width is equal to 0.9, the natural frequency before seepage stage and the third one is after the highest. The second high one is before seepage stage and the third one is after earthquake and the smallest one is predominant frequency of the dam under Chi-Chi earthquake. The natural frequency of the core is lower than those of crusts on the upstream and downstream. | ||
| 檔案： | 沒有相關檔案 | |
| 相關連結： | http://ethesys.lib.cyut.edu.tw/ETD-db/ETD-search-c/view_etd?URN=etd-0828108-183626 | |