巖土工程中非飽和土膨脹土隆起變形分析方法主要包括經(jīng)驗(yàn)法、固結(jié)試驗(yàn)法、吸力法和數(shù)值法。多物理場(chǎng)耦合分析數(shù)值法因具有考慮因素多、處理復(fù)雜問(wèn)題能力強(qiáng)等諸多優(yōu)勢(shì),廣泛用于土體多物理場(chǎng)耦合復(fù)雜分析的問(wèn)題中。為了準(zhǔn)確分析并預(yù)測(cè)非飽和膨脹土隆起變形的問(wèn)題,本文基于水-熱-力耦合理論方法,研究并建立求解非飽和膨脹土隆起變形的偏微分方程組與相應(yīng)的數(shù)值模型。據(jù)此,開(kāi)展了如下主要研究工作。(1)采用非飽和土力學(xué)理論,考慮基質(zhì)吸力、土體變形和熱對(duì)流的耦合作用,建立了非飽和膨脹土水-熱-力耦合分析的數(shù)學(xué)偏微分方程(即:土的變形方程、孔隙水流動(dòng)方程和溫度方程),能夠用于分析含水量和溫度等不同環(huán)境條件變化下非飽和膨脹土膨脹和干燥過(guò)程中應(yīng)力和變形的問(wèn)題。(2)在多物理場(chǎng)仿真軟件COMSOL Multiphysics將非飽和膨脹土水-熱-力耦合分析的數(shù)學(xué)偏微分方程,進(jìn)行了有限元法數(shù)值實(shí)現(xiàn),并通過(guò)抽水引起膨脹土場(chǎng)地變形、膨脹土逐漸潤(rùn)濕引起土體變形的實(shí)測(cè)數(shù)據(jù)驗(yàn)證了數(shù)值模型的正確性,并與水-力耦合理論分析結(jié)果進(jìn)行了對(duì)比,得到水-熱-力耦合理論分析結(jié)果更準(zhǔn)確。(3)系統(tǒng)分析了不同邊界條件膨脹土的泊松比和溫度對(duì)膨脹土變形的影響,...

【文章頁(yè)數(shù)】：96 頁(yè)

【學(xué)位級(jí)別】：碩士

【文章目錄】：
摘要
Abstract
List of Acronyms
Chapter 1 Introduction
    1.1 Description of the Topic
    1.2 Statement of the Problem
    1.3 Objectives of the Study
    1.4 Outline of the Thesis
    1.5 Background of Expansive Clay Soil
        1.5.1 Identification of Expansive Soil
        1.5.2 Structure of Expansive Clay Soil
    1.6 Mechanical Behavior of Expansive Soil
        1.6.1 Stress State Variables
        1.6.2 Constitutive Relationships
    1.7 Literature Review on Heave Prediction Methods
        1.7.1 Empirical Methods
        1.7.2 Methods Based on Oedometer Tests
        1.7.3 Methods Based on Suction Method
    1.8 Coupled and Uncoupled Approaches
        1.8.1 Coupled Approach
        1.8.2 Uncoupled Approach
    1.9 Significance of the Research
    1.10 Summary
Chapter 2 Theory Framework of the Heave of Expansive Soil Considering CoupledThermo-Hydro-Mechanical Analysis
    2.1 Introduction
    2.2 Flow Laws for Expansive Soils
        2.2.1 Air Flow Law for Expansive Soils
        2.2.2 Water Flow Law for Expansive Soils
    2.3 Theory of Numerical Modelling
        2.3.1 Soil Equilibrium Equation
        2.3.2 Water Flow Law
        2.3.3 Thermal Flow Law
    2.4 Governing Partial Differential Equations
        2.4.1 Partial Differential Equation for Soil Deformation
        2.4.2 Partial Differential Equation for Water Flow
        2.4.3 Partial Differential Equation for Heat Flow
    2.5. Finite Element Modeling for Coupled Thermo-Hydro-Mechanical analysis
        2.5.1 Strain-Displacement Relationship
        2.5.2 Soil Equilibrium Equation Finite Element Formulation
        2.5.3 Water and Heat Flow Equation Finite Element Formulation
    2.6 Summary
Chapter 3 Verification and Analysis of Numerical Modeling
    3.1 Introduction
    3.2 Numerical modeling using coupled Hydro-Mechanical Analyses and Coupled Thermo-Hydro-Mechanical Analyses
        3.2.1 Computer Program COMSOL Multiphysics 5.3
        3.2.2 Cases Presentation
    3.3 Verification and Discussion of the Modeling
        3.3.1 Results and Discussion for Case 1
        3.3.2 Results and Discussion for Case 2
    3.4 Summary
Chapter 4 Parametric Study
    4.1 Introduction
    4.2 Parametric Study Related to the Change of the Poisson’s Ratio in Case1
    4.3 Parametric Study Related to the Change of the Boundaries Conditions and thePoisson’s Ratio in Case 2
    4.4 Summary
Chapter 5 Conclusions and Future Works
    5.1 Conclusions (English)
    5.2 Conclusions (Chinese)
    5.3 Future Works
References
Acknowledgement



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