| 姓名 | 王少濂(Shao-Lien Wang) | 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 | 91學年第2學期 | |
| 論文名稱(中) | 砂土中擴座地錨互制行為之研究 | |||
| 論文名稱(英) | A Study on the Interactive Behaviour of Underreamed Anchors in Sand | |||
| 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 | 校內外完全公開 | |
| 論文語文/頁數 | 中文/202 | |||
| 摘要(中) | 本研究利用數值分析和模型試驗探討雙錨在緊砂中於不同水平間距下之互制行為。數值分析係藉由FLAC3D軟體並配合SHSE模式來進行，並將數值分析之結果與模型試驗比較，以確立數值分析之正確性，進而探討砂土中模型雙錨錨碇力受水平間距之影響情況。 研究結果顯示，數值分析與模型試驗結果大致吻合。依面承力係數之定義方式可將覆土深徑比Z/D＜7時定義為淺層地錨、Z/D=7~14為轉換地錨和Z/D＞14為深層地錨。淺層地錨面承力具有明顯之尖峰值，而深層地錨面承力則無明顯之尖峰值，深層地錨之降伏面承力Qqy所對應之位移量約為25%的地錨直徑。地錨達尖峰摩擦力下之側向土壓力係數Kf約為1.47，且略隨覆土深度之增加而減少；而殘餘摩擦力下之側向土壓力係數則小於靜止土壓力係數K0。 當覆土深徑比Z/D=4和Z/D=10時，地錨拉拔力和摩擦力在水平間距比Sh/D=7、面承力則在水平間距比Sh/D=10時可忽略群錨效應之影響。當覆土深徑比Z/D=16時，在水平間距比Sh/D≧6後地錨拉拔力、摩擦力和面承力可忽略群錨效應的影響，本研究亦更進一步地建立了不同覆土深度下水平間距與群錨效應係數間的關係，以供設計者使用。研究亦發現，不論深層或淺層地錨在水平間距比Sh/D=2時，尖峰拉拔力下土壤之降伏範圍具有高度重疊現象，介於兩地錨錨碇段間之土壤則大多仍維持在彈性階段且隨著錨碇段之移動而移動；隨著水平間距的增加，土壤降伏範圍之重疊區域逐漸減少，最後趨於各自獨立之降伏範圍。 | |||
| 摘要(英) | Numerical analyses
and model tests were performed to study the uplift behavior of
individual anchors and paired anchors in dense sand. A constitutive
model named “SHSE” was used in the FLAC3D software to simulate the
behavior of dense sand. To emphasize the applicability of the numerical
model, results of numerical analyses were verified by results from model
anchor tests. It was found that the load-displacement behaviors calculated by the numerical method were closed to model anchor tests not only for individual anchors but also for paired anchors. Based on the definition of end resistance coefficient, when the overburden-diameter ratio Z/D<7 can be defined as a shallow anchor, when Z/D=7~14 is classified to a transited anchor, when Z/D>14 is belong to a deep anchor. The peak end bearing can be found in shallow anchors but not in deep anchors. The yielding end-resistance of depth anchor develops at a displacement of 25%D. The coefficient of lateral earth pressure Kf equals to 1.47 and slightly decreased with overburden depth when an anchor reaches its peak friction. The coefficient of earth pressure at residual friction Kr is less than the coefficient of earth pressure at rest K0. When overburden depth of anchors equal to 4D~10D, there will be virtually no group effect for total load and friction force if anchors are placed 7D horizontally apart, and 10D horizontal space can eliminates the influence of end resistance. We can treat paired anchors as two independent anchors, if the overburden depth of them equal to 16D and placed more than 6D apart horizontally . A series of design figures of group effect was then established based on the numerical results of paired anchors. The yielding zone of the two anchors overlap if they are placed 2D horizontally apart. Soils between pair anchors remain elastic and moves together with fixed end of the anchor. The overlap of yielding range decreases with increasing horizontal space. Finally, as the horizontal spacing of paired anchors is greater than a critical value, the two anchors tend to develops independent yielding zone. | |||
| 關鍵字(中) |
|
關鍵字(英) |
| |
| 指導教授 |
| |||