| 姓名 | 李寬然(Kuan-Jan Li) | 電子郵件信箱 | E-mail 資料不公開 | |
| 畢業系所 | 營建工程系碩士班(Department and Graduate Institute of Constrction Engineering) | |||
| 畢業學位 | 碩士(Master) | 畢業時期 | 95學年第2學期 | |
| 論文名稱(中) | 飽和砂質土壤二次液化相關性質之研究 | |||
| 論文名稱(英) | Study of Re-liquefaction Behavior of Saturated Granular Soils | |||
| 檔案 |
請遵守中華民國著作權法之相關規定，切勿任意重製、散佈、改作、轉貼、播送，以免觸法。 |
論文使用權限 | 校內外均一年後公開 | |
| 論文語文/頁數 | 中文/76 | |||
| 摘要(中) |
本研究利用土壤液化箱並利用小型震動台，做震動液化試驗來探討飽和砂質土壤對二次液化的影響及相關行為研究。 研究結果顯示飽和砂質土壤在相對密度低時(<45%)的狀態下容易發生二次液化，當飽和砂質土壤在相對密度60％以上，發生二次液化所需之震動能量與一次液化能量比值N約為相對密度30％時的能量比值N的2∼3倍，當土壤的排水速率提高時，所需要的震動比值N也會提高，但是沉陷量εv卻是下降；液化間隔時間增加時，土壤所需要的震動能量比值N也會相對提昇，而沉陷量εv則會下降。本實驗結果顯示若土壤在相對密度高(>60%)、排水速率快、液化間隔時間長時，其二次液化所需要的震動能量是一次液化能量增加可達50倍以上（有時甚至沒有二次液化），而其液化後沉陷量卻顯著降低甚至其沉陷量接近於零。 最後本研究建立了一套概估飽和砂質土壤一次及二次液化能量比值N之經驗公式：N≒28*(CDr)*(C排水)*（C液化間隔時間），希望藉由此公式能在未來工程實務界與學術研究單位能有所幫助。 |
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| 摘要(英) | The
study used portable shaking table and soil liquefaction tank to
study the re-liquefaction characteristics of saturated granular
soils. Results of the study indicated that sandy soils is prone to re-liquefaction when the relative density Dr is less than about 40%, while the energy ratio N, defined as the ration between the energy required to cause the re-liquefaction and the first liquefaction, at Dr=60% is 2-3 times of that at Dr=30%. This implies that as Dr increases the energy required for re-liquefaction is also significantly increased. The study results also revealed that the seepage rate within the soil deposit is also an important factor: as the seepage rate increases, the energy ratio N increases while the resulting volume strain (settlement) decreases. In addition, when the time elapsed between the first and re-liquefaction increases, the energy ratio N also increases as settlement decreases. The study results showed that for the sandy soils at great Dr (>60%) and seepage rate, and longer elapsed time, the energy required for the re-liquefaction can be as high as more than 50 times of the first liquefaction, sometimes even no re-liquefaction occurred in the study while the resulted settlement is significantly reduced, in some cases close to zero (no settlement). The study also derived an empirical equation for estimating the energy ratio, with parameters related to Dr, seepage rate and elapsed time, as shown below hopefully to provide useful information for academic research and practical applications: N=28 x (C Dr) x (C seepage) x (C elapsed time) |
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| 口試日期 | 2007-07-13 | 繳交日期 | 2007-07-15 | |