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論文中文名稱:不飽和土壤流固耦合案例分析與探討 [以論文名稱查詢館藏系統]
論文英文名稱:Case study of unsaturated soil via hydro-mechanical coupled analysis [以論文名稱查詢館藏系統]
院校名稱:臺北科技大學
學院名稱:工程學院
系所名稱:土木工程系土木與防災碩士班
畢業學年度:106
畢業學期:第二學期
出版年度:107
中文姓名:劉顥鈞
英文姓名:Hou-Guen Lau
研究生學號:105428408
學位類別:碩士
語文別:英文
口試日期:2018/07/19
論文頁數:108
指導教授中文名:魏敏樺
口試委員中文名:陳卓然;張榮峰
中文關鍵詞:不飽和土壤數值分析降雨入滲邊坡穩定性壓密真空加載
英文關鍵詞:unsaturated soilnumerical analysisrainfall-infiltrationslope stabilityconsolidationvacuum-drain
論文中文摘要:至今,飽和土壤的土壤行為的經典理論已發展相當完善且技術已成熟應用於民生經濟上,多數成功解決地土結構加載所產生的地表沈陷、地下水滲透,成功推測邊坡的滑動等問題,但不飽和土壤行為與力學機制,普遍都為實驗物性研究,少有使用數值分析軟體探討不飽和土壤的案例文獻,因此本研究使用有限元素數值分析軟體探討不飽和土壤之邊坡穩定與壓密案例。本研究為了驗證有限元素數值分析軟體之結構力學模組與地下滲流模組在不飽和土壤上之耦合分析,透過修改不飽和方程與輸入不飽和土壤參數,分別檢視其應力狀態,應變位移,超額孔隙水壓分佈,飽和度等物理量。案例分析首先實踐不飽和邊坡穩定在降雨下之表現,得知其在滲透下之破壞滑動面、變位滑動量與孔隙水壓分佈,使用強度折減法計算出各參數案例的安全係數;然後再應用在真空壓密之土壤改良案例上,得知其沉陷行為與超額孔隙水壓之消散行為,最終得知其沉陷量與孔隙水變化。
論文英文摘要:Up to now, the classical theory of the behavior of saturated soil has been very well developed and applied to mankind economy. They have successfully solved problems of settlement and groundwater infiltration caused by soil structure loading, and successfully predicted the problem of slope failures. However, the behavior and mechanism of unsaturated soil were generally studied as experimental physical properties, and the case literature of unsaturated soil via numerical analysis is stay rare. Therefore, this study used finite element analysis to explore the slope stability and consolidation of unsaturated soil. To verify the coupling effect in finite element analysis on unsaturated soil, the stress state, displacement, pore-water pressure distribution, saturation and other physical quantities were examined a series of parametric study. Firstly, the performance of unsaturated slope stability under rainfall was first studied, and evaluated its failure sliding surface, displacement and pore-water pressure distribution under infiltration. were known. The case of soil improvement under vacuum consolidation to examine its subsidence behavior, pore-water pressure dissipation behavior, and predicted its settlement period and the change pore-water pressure.
論文目次:摘 要 i
Abstract ii
誌謝 iv
Table of Contents v
List of Tables viii
List of Figures x
Chapter 1 Introduction 1
1.1 General 1
1.2 Objectives of Study 2
1.3 Methodology 2
1.4 Layout of Thesis 3
Chapter 2 Literature Review 5
2.1 Introduction 5
2.2 Composition of Unsaturated Soil 5
2.3 Theory of Unsaturated Soil 7
2.3.1 Theory of Soil Suction 7
2.3.2 Soil-Water Characteristic Curve 9
2.3.3 Predicting the Hydraulic Conductivity of Unsaturated Soils 14
2.4 Shear Strength of Unsaturated Soil 16
2.5 Strength reduction method 18
2.6 Field consolidation – Vacuum-drain method 18
Chapter 3 Method and Verification 21
3.1 Introduction 21
3.2 Solid mechanics module 21
3.3 Subsurface flow module 24
3.3.1 Darcy’s Law 24
3.3.2 Richards’ Equation 26
3.4 Boundary Conditions and Initial Conditions 30
3.5 Verification of the analysis 31
3.5.1 Modeling flow chart 31
3.5.2 Modeling 32
3.5.3 Verification results 35
Chapter 4 Slope Stability Analysis 37
4.1 Background 37
4.2 Constitutive Equation 42
4.2.1 Equilibrium Equation 42
4.2.2 Richards’ Equation 42
4.3 Coupled Slope Stability Analysis 43
4.3.1 Input parameters 46
4.3.2 Modeling and mesh creating 48
4.3.3 Steady-state and Time-dependent analysis 50
4.4 Coupled analysis with strength reduction method 56
4.5 Parametric studies 64
4.5.1 Effect of slope height 64
4.5.2 Effect of slope angle α 65
4.5.3 Effect of rainfall duration 65
4.6 Summary 72
Chapter 5 Vacuum consolidation analysis 73
5.1 Case Study 73
5.2 Governing equation of consolidation 78
5.3 Simulation of Vacuum Consolidation 79
5.4 Parametric study 89
5.4.1 Effect of PVDs 89
5.4.2 Effect of groundwater level 92
5.4.3 Comparison of PVDs spacing 94
5.4.4 Effect of vacuum pressure (V.P.) 96
Chapter 6 99
6.1 Conclusions 99
6.2 Recommendations 101
References 103
List of Symbols and Abbreviations 107
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論文全文使用權限:同意授權於2023-08-20起公開