鄭富書林銘郎臺灣大學:鄭添耀Jeng, Tian-YaoTian-YaoJeng2007-11-252018-07-092007-11-252018-07-092007http://ntur.lib.ntu.edu.tw//handle/246246/50287本研究採用數值方法針對褶皺構造在曲滑作用下的力學行為進行分析。在前人的研究中,已成功推導出單層與複層褶皺的彈性理論解,惟理論背景有相當的簡化,無法全然的反應出自然界所見褶皺軸部產生破碎空洞、層面間相互滑動產生擦痕之地質構造,故本研究以前人提出之彈性理論解為基礎,使用彈塑性材料進行模擬比對,並探討曲滑作用對褶皺構造之影響,最後以分離元素法進行褶皺大變形行為之模擬,期望能更近似的模擬自然界所見之褶皺構造。 研究結果顯示:彈塑性褶皺生成後繼續壓縮,則褶皺軸的位置會產生變動而造成波數的增加,波長的減短。對振幅衰減波型之褶皺構造而言,受到岩層彈塑性行為的影響,提早產生挫屈形成雙頻褶皺,波數增加,波長有減短的趨勢。 褶皺軸部空洞(cavity)的產生和界面摩擦性質有助於岩層挫屈時,褶皺振幅的增長。褶皺軸部空洞的產生,使得介質反力下降,褶皺生成時低頻波長因而有增長的趨勢,但界面摩擦性質有助於彌補介質反力的損失。 曲滑作用在複層褶皺的模擬,成功的印證Currie et al. (1962)所提出以能量法推導得複層褶皺之理論公式,界面摩擦性質有助於增加所對應的單層等效層厚,促使褶皺生成時高頻波長增長,低頻波長減短。 由分離元素法模擬褶皺之發育,可成功的將褶皺的發育階段分成四個時期:(1)預壓縮階段。(2)岩層挫屈生成圓弧褶皺,褶皺軸部為了調適空間而產生空洞。(3)圓弧褶皺變形為尖頂褶皺,軸部產生塑性鉸。(4)褶皺軸部的破裂造成強度的喪失,褶皺開始壓扁變形,軸部的空洞閉合。The flexural slip folding of buckling folds is studied based on numerical analyses. In previous studies, the elastic theoretical solutions of single layer and multilayer folds have been formulated. However these analytical solutions are based on simplifications. Some of the geological structures in the field, such as the hinge cavity of folds and the slickenside formed by flexural slip folding are still awaiting for further exploration regarding the mechanism. In this research, elasto-plastic material was adopted in numerical simulation and compared with the elastic theoretical solution. The influence of flexural slip folding on folds is then discussed as well. In the end, simulation of the large deformation behavior of folds was conducted by using bonded particle model. The results of study show that: For an unconstrained elasto-plastic layer under compression, the wavelength can be shortened in post-buckling stage. As to folds with decaying amplitude, the elasto-plastic behavior leads to an early buckle folding and shortens the wavelength. The appearance of cavity results in reduction of the reactive force exerted by the matrix and increases the low-frequency wavelength; on the other hand, the interface friction can counteract the effect. The flexural slip model of multilayer folds compares well with the theoretical solution by Currie et al. (1962). For multilayer folds, the interface friction tends to increase the high-frequency wavelength and shorten the low-frequency wavelength. Cavity and interface friction tend to increase the amplitude of fold. From the simulation of fold growth by bonded particle model, it can be divided into four stages:1. Initial compression stage; 2. Circular fold yielded and cavity was formed; 3. The plastic hinge was formed, then circular fold turned into chevron folds; and 4. The folds were flattened and the cavity was filled with matrix.口試委員會審定書 I 摘 要 II Abstract III 符號表 V 目錄 VI 表目錄 IX 圖目錄 X 第一章 緒論 1 1.1 研究背景 1 1.2 研究目的與方法 2 1.3 本文內容 2 第二章 文獻回顧 5 2.1 彈性材料的褶皺理論 5 2.1.2 複層岩層的褶皺理論 8 2.2 尖頂褶皺的行為模式 9 2.3 曲滑作用的行為模式 10 2.4 褶皺的發育過程 11 第三章 研究方法 19 3.1 分析軟體簡介 19 3.1.1 分析軟體-ABAQUS概述 19 3.1.2 分析軟體-PFC概述 20 3.2 有限元素分析方法 20 3.2.1 數值分析模型介紹 20 3.2.2 數值分析模型規劃 21 3.2.3 材料參數的選定 21 3.3 分離元素分析方法 24 3.3.1 數值模型介紹 24 3.3.2 微觀參數與宏觀參數之轉換 25 第四章 單層褶皺的彈塑性行為 31 4.1 數值模型介紹 31 4.2 單一岩層所產生之褶皺構造 31 4.3 有介質岩層所產生之褶皺構造 33 4.3.1 預壓縮量對彈塑性褶皺構造之影響 33 4.3.2 彈性阻抗比對彈塑性褶皺構造之影響 34 第五章 曲滑作用對褶皺之影響 48 5.1 數值模型介紹 48 5.2 界面性質對單層褶皺構造之影響 48 5.2.1 不同波型對滑動帶正向分離、切向滑動之影響 48 5.2.2 界面性質對褶皺振幅之影響 49 5.2.3 界面性質對褶皺波長之影響 49 5.3 界面性質對複層褶皺構造之影響 50 5.3.1 界面性質對褶皺波長之影響 50 5.3.2 岩層厚度對褶皺波長之影響 51 第六章 應用分離元素法於褶皺之模擬 59 6.1 顆粒粒徑對單壓強度與彈性模數之影響 59 6.2 材料參數 59 6.3 二維模型之建立 60 6.4 模擬結果 60 6.5 考慮覆土壓力之影響 61 第七章 結論與建議 69 7.1 結論 69 7.2 建議 70 參考文獻 71 附錄A PFC運算原理 A-1 附錄B ABAQUS界面元素簡介 B-1 附錄C PFC於褶皺模擬可行性分析 C-1 附錄D 論文口試-問題與回覆 D-114256376 bytesapplication/pdfen-US尖頂褶皺曲滑作用挫屈彈塑性界面性質數值模擬chevron foldflexural slipbuckleelasto-plasticinterface propertiesnumerical simulation褶皺的曲滑作用模式數值模擬初探Flexural Slip Model of Buckling Folds -Numerical Simulation & Analysisthesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/50287/1/ntu-96-R94521124-1.pdf