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碩士論文公告區 |
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| 年度： | 91 | |
| 姓名： | 李明翰(Ming-Han Li) | |
| 論文題目(中)： | 岩坡傾倒破壞之研究-以台14線公路為例 | |
| 論文題目(英)： | Study of Toppling Failure of Rock Slopes along Taiwan Highway No. 14. | |
| 摘要(中)： | ||
| 台灣地區由於惡劣之地質狀況及嚴酷的氣候，使得邊坡穩定問題十分的重要。傾倒破壞通常發生於層狀岩體之逆向坡，如薄層沉積岩、葉理狀變質岩及其它含有單組節理之岩石。由於此種破壞過程十分漫長因此傾倒破壞在台灣地區並未受到重視。而在921地震時中部山區道路邊坡破壞種類中，落石及岩坡傾倒破壞高居第二位，因此，有其必要了解岩坡傾倒之破壞。本文主要選擇台14線74K之兩處已傾倒之岩坡進行分析，以了解其破壞影響因子。 本文以分離元素法為主的數值程式UDEC，來針對台14線74K兩處已傾倒之岩坡進行反推分析與模擬，找出其破壞原因，並使用UDEC來進行一連串數值實驗，以了解現地岩坡傾倒破壞之機制與影響因子。 台14線74K兩處傾倒邊坡屬於脊樑山塊地質區中部，主要由板岩及硬頁岩組成。由UDEC程式分析結果顯示，案例一之岩坡破壞模式與坡趾遭受侵蝕或開挖較吻合；案例二則為風化作用與覆土載重導致岩坡發生傾倒。在破壞模式方面，硬質岩坡近坡趾處並未有明顯之塑性破壞也沒有傾倒破壞之傾向，與一般軟質岩坡破壞模式不同。在影響因子方面，當風化作用產生之岩橋長度及連續性、覆土載重增加時，岩坡之弱面摩擦角為了維持岩坡之穩定性而增加。在案例二參數研究之結果顯示，岩橋長度小於4m及岩橋連續性在30%~70%時，覆土載重比岩橋長度及連續性對岩坡穩定性之影響較為顯著。當岩橋長度在6m及岩橋連續性在30%~70%時，則岩橋長度及連續性比覆土載重較易影響岩坡之穩定性。 |
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| 摘要(英)： | ||
| Because of steep topography, inferior geological condition and severe climate, slope instability is always a serious problem in Taiwan. Common failure modes of rock slopes are composed of planar, wedge, toppling and circular. Toppling failure always occurs in anaclinal slopes of layered rock mass, such as thin-bedded sedimentary rocks, foliated metamorphic rocks and those of one single joint set. Because its failure process is quite long, toppling has not been well noticeable in Taiwan. Among the types of slope failures, the number of damages due to rock falls and toppling failures was ranked the second during 921 earthquake. Therefore, had to understanding the failure of toppling of rock slopes. Numerical analyses using UDEC (a program based on distinct element method) will be used to analyze two rock slopes of the toppling that on Highway 14 to understand the failure mechanisms. The Highway 14 chosen for illustrative purpose is located in the middle part of Geologic Region, and its route is mainly covered by slate and argillite. The results of analyses using UDEC indicate that: the failure modes of rock slopes are correspond to erosion or excavate toe of slopes on case 1, and rock slopes was toppled by weathering and an overburden load on case 2. The hardness rock slopes were neither plastic deformation nor tend to toppling, that were different from weak slopes of failure modes. When Rock Bridge of length, Rock Bridge of continuity and an overburden load to increase, friction angle of joints of rock slopes to increase for stable. The results of parametric study indicate that : when Rock Bridge of length less then 4m and Rock Bridge of continuity between 30%~70%, an overburden load is effect more then Rock Bridge of length and Rock Bridge of continuity. When Rock Bridge of length greater then 6m and Rock Bridge of continuity between 30%~70%, the Rock Bridge of length and Rock Bridge of continuity is effect more then an overburden load. |
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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-0827103-142942 | |