請用此 Handle URI 來引用此文件:
http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/36441
標題: | 車籠埔斷層周圍岩石力學特性之初探 |
作者: | Cheng-Wang Chen 陳正旺 |
指導教授: | 鄭富書(Fu-Shu Jeng) |
共同指導教授: | 林銘郎(Ming-Lang Lin) |
關鍵字: | 車籠埔斷層,純剪應力路徑,加溫實驗, Chelungpu-fault,pure shear stress path test,temperature, |
出版年 : | 2005 |
學位: | 碩士 |
摘要: | 一般以數值分析模擬斷層錯移演繹時,首要條件即為取得斷層圍岩之材料參數,但是以往受限於地底岩層材料之取得性困難,因此前人研究大多是以地表露頭所取得之岩石進行力學實驗,以求得代表某一地層之材料參數。但除了地表受風化之岩石與地底新鮮岩石間之力學特性有待釐清之外,在真實情況下,相同地層中,岩石之岩性會隨深度而變化,因此若將地層視為單一岩性,將無法適當的描述地層之強度與變形特性。
本研究配合TCDP鑽探計畫,可取得地表下新鮮且完整之斷層周圍岩石進行力學試驗,並配合草嶺地表所取得之卓蘭層試體進行比較,可進一步探討岩石隨深度之變化,其力學特性之差異。此外,前人之研究大多是在室溫狀態下進行實驗,然而未來工程施工條件勢必遭遇需考量溫度效應之環境,因此考量溫度效應對於岩石力學特性之影響,亦為本研究探討的課題之一。 本研究依據地層柱,將岩石分為四大類型,I類型為地表卓蘭層;Ⅱ類型為生物擾動段;Ⅲ類型為粗顆粒砂岩;Ⅳ類型則為粉砂岩,以進行力學實驗。研究結果顯示,在變形特性方面,主要是受到孔隙率影響,孔隙率大之岩石變形量會較孔隙率低之岩石為大,亦即岩石之變形特性受岩性影響較大,而與深度之相關性不顯著。而在溫度效應方面,實驗成果顯示在本研究120度加溫範圍內,溫度對於岩石力學強度及彈塑行為之影響並不顯著,即未來工程上若遭遇到在此溫度範圍內之地熱區域,則只需要針對施工方式進行考量,而岩石本身之強度與變形性則無需考慮溫度效應。 最後,本研究亦採用可合適描述岩石非線性彈性及諧和性準則之彈塑組成模式,模擬結果顯示,本研究所採用之組成模式能適當描述I及Ⅲ類型岩石彈塑性應力-應變行為,且與實驗資料有不錯之吻合。 Generally, in order to study the mechanical characteristic of the strata, we often measure the physical and mechanical properties of the specimens took from the surface of the earth. In the real case, the rocks’ characteristic changed by the depth and the properties. If we took the rocks to a single property, it can not describe the strength and deformation of the strata completely. In this study, we research the mechanical characteristic of the specimens of two source. One is the Cholan sandstone which was took from Cao-ling, the other is the cores with a depth ranging from 450 to 1300m from TCDP program. Accordingly, the specimens are subjected to a series of mechanical experiments, including stress-path controlled pure shear tests to study their physical properties as well as their strengths and deformability with elastic and plastic strained being distinguished. Meanwhile, temperature factor are also conducted so as to study the influence on the rocks. According to the experimental results, we can found that the Drucker- Prager failure criteria can describe the failure envelop line of rocks applicably, and the stress-path and strength of rocks are not related. It was also found that the rocks with lower porosities exhibit larger deformation than rocks with higher porosities. According to the notion of distinguishing the deformation from elastic and plastic components, it can describe the behavior of rocks subjected to volumetric stress and shear stress applicably, including the non-linear elastic deformation ,plastic strain locking, the elastic volumetric strain was coupled with shear stress. As to the temperature factor, the influence of the factor on rocks was not very apparent in this research. Finally, according to the constitutive model of sandstone, we can obtain the parameters of the elastic and plastic model, then we can predict the stress-strain curve of rocks and compare with the data from pure shear triaxial test. According to the analysis, we can find that the constitutive model can applicably describe the deformable characteristic of rocks of type I and type Ⅲ. |
URI: | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/36441 |
全文授權: | 有償授權 |
顯示於系所單位: | 土木工程學系 |
文件中的檔案:
檔案 | 大小 | 格式 | |
---|---|---|---|
ntu-94-1.pdf 目前未授權公開取用 | 3.42 MB | Adobe PDF |
系統中的文件,除了特別指名其著作權條款之外,均受到著作權保護,並且保留所有的權利。