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碩士論文公告區 |
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| 年度： | 89 | |
| 姓名： | 洪正杰(Cheng-Jie Hung) | |
| 論文題目(中)： | 沈泥質砂土中拉力樁與壓力樁荷重行為之差異 | |
| 論文題目(英)： | The Loading Behavior of Tensile Piles and Compressive Piles in Silty Sand | |
| 摘要(中)： | ||
| 本研究主要目的在於利用數值分析配合現場試驗之方式探討沈泥質砂土中壓力樁與拉力樁之受力行為。研究進行之方式係沿用先前沈泥質砂土三軸試驗數據，加以應用至SHSE模式(描述砂土應變硬化-軟化及受剪膨脹行為)，配合FLAC軟體進行沈泥質砂土中壓力樁與拉力樁之數值分析，並利用數值分析和現場試驗結果建立基樁之總承載力、摩擦力、點承力與位移間之評估公式與相關之設計圖表，以提供大地工程師設計基樁時之參考。 數值分析之主要內容包括：(1)壓力樁與拉力樁受力行為之比較；(2)壓力樁與拉力樁總承載力、摩擦力、點承力與樁頭位移間之關係；(3)基樁直徑、長度及砂土相對密度對於基樁承載力之影響；(4)荷重沿基樁之傳遞情形；(5)摩擦應力沿樁身之分佈情形；(6)基樁周圍土壤之降伏情形；(7)基樁周圍土壓力隨承載力之變化情形。 經由數值分析結果可明顯看出壓力樁及拉力樁之承載力、摩擦力與點承力皆因應著樁徑、樁長及砂土之相對密度而變化。因此本研究將基樁之承載力、摩擦力及點承力表示成砂土之相對密度Dr及長徑比L/D之函數，並將之撰寫成預測程式後，不但可大量縮短數值分析之運算時間，而且與現場基樁之試驗結果進行驗證時亦可得到滿意之結果。 |
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| 摘要(英)： | ||
| Both numerical analysis and field tests have been performed to study the behavior of compressive and tensile piles in silty sand. A Strain Hardening-Softening and volume Expansion model called "SHSE" for silty sand will be adopted to establish the parameters need for SHSE model from triaxial test. The model and FLAC software are used to carry out the numerical analysis for piles. Based on the numerical results, a series simple calculated formulas and design charts among the total load, skin friction and end resistance with respect to displacement of pile head have been established for designer. The major subject in this study includes: (1) Comparison of load capacity between tensile pile and compressive pile. (2) The relationship among Total load, shaft capacity and end-bearing capacity with respect to displacement of pile head. (3) The influence of load capacity by the diameter, length of pile and the relative density of silty sand. (4) The load transferring along the pile. (5) The distribution of frictional stress around pile shaft. (6) The yielding conditions of soil around pile. (7) The variation of earth pressure around the pile depends on the load. The results have shown that the diameter of pile, the length of pile and the relative density of sand could affect the total load, shaft friction and end bearing of pile. In order to reduce the time consumption of numerical study, the relationship between load and displacement of pile are correlated with the relative density of sand, the diameter of pile, and the length of pile. A simple program was then established which can significantly cut down the compute time. In addition, the load-displacement behavior predicated by the program is very closed to the field test not only compressive pile but also tensile pile. |
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| 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-0827102-155642 | |