Hydro-mechanical Analysis of Rainfall-lnduced Landslides

1 Background 1£®1 Physical Properties of Unsaturated Infiltration 1£®1£®1 Basic Physical Properties 1£®1£®2 Soil Suction 1£®1£®3 Unsaturated Hydraulic Conductivity 1£®1£®4 Total Head 1£®1£®5 Soil-Water Characteristic Curve 1£®2 Governing Equation of Water Infiltration 1£®2£®1 Richards' Equation 1£®3 Shear Strength and Slope Stability 1£®3£®1 Unsaturated Shear Strength 1£®3£®2 Slope Stability References 2 Analytical Solution to 1D Coupled Infiltration and Deformation in Unsaturated Porous Media 2£®1 Introduction 2£®2 Effect of Rainfall Pattern 2£®2£®1 Governing Equations for Coupled Seepage and Deformation 2£®2£®2 Analytical Solutions to 1D Coupled Infiltration Problems Before and After Ponding 2£®2£®3 Examples and Analysis Results 2£®2£®4 Conclusions 2£®3 Effect of Boundary Condition 2£®3£®1 Coupled Infiltration Equations 2£®3£®2 Solution for Infiltration into Deformable Soils 2£®3£®3 Example 2£®3£®4 Conclusions 2£®4 Effect of Layered Structure 2£®4£®1 Governing Equations 2£®4£®2 Parametric Study 2£®4£®3 Conclusions Appendix References 3 Effects of Gravity and Hysteresis on 1D Unsaturated Infiltration 3£®1 Introduction 3£®2 Effect of Gravity 3£®2£®1 Governing Equation 3£®2£®2 Boundary and Initial Conditions 3£®2£®3 The Analytical Solutions for Transient Unsaturated Infiltration 3£®2£®4 The Analytical Solution for Steady Unsaturated Infiltration 3£®2£®5 Case Study and Analysis 3£®2£®6 Summary 3£®3 Effect of Hysteresis 3£®3£®1 Brief Review of Hysteretic Soil-Water Characteristic Models 3£®3£®2 Mathematical Formulations for Hysteresis 3£®3£®3 Analytical Solutions Considering Hysteresis 3£®3£®4 Analysis Examples 3£®3£®5 Conclusions 3£®4 Effect of Semi-infinite Region 3£®4£®1 Governing Equation 3£®4£®2 Parametric Study 3£®4£®3 Conclusions References 4 2D Infiltration in Unsaturated Porous Media 4£®1 Introduction 4£®2 Analytical Solution to Finite Domain 4£®2£®1 Governing Equation of Coupled Infiltration Problems 4£®2£®2 Formulation of the Initial Value Problem 4£®2£®3 Analytical Solutions to Two-Dimensional Coupled Infiltration 4£®2£®4 Numerical Results 4£®2£®5 Conclusions 4£®3 Numerical Solution to Water Table Rise 4£®3£®1 Governing Equations for the Hydromechanical Processes Involved in Water Table Change 4£®3£®2 Computational Modeling 4£®3£®3 Examples of Water Infiltration 4£®3£®4 Discussion and Conclusions 4£®4 Surface Infiltration in Semi-infinite Extent 4£®4£®1 Governing Equations for Coupled Seepage and Deformation in Unsaturated Soils 4£®4£®2 Analytical Solution to the Coupled Infiltration in a Semi-infinite Region 4£®4£®3 Computational Modeling of Water Infiltration in a Semi-infinite Unsaturated Region 4£®5 Conclusions References 5 Physical Simulation of Rainfall Infiltration into Unsaturated Slopes 5£®1 Introduction 5£®2 Physical Testing of Rainfall-Induced Loose Deposit Slope Failures 5£®2£®1 Model Design 5£®2£®2 Analysis of the Slope Model Experiments 5£®2£®3 Conclusions 5£®3 Laboratory Simulation of Rainfall-Induced Loess Slope Failure 5£®3£®1 Methods 5£®3£®2 Results and Analysis 5£®3£®3 Numerical Analysis 5£®3£®4 Conclusions 5£®4 Model Test for Rainfall-Induced Shallow Landslides in Red-Bed Area 5£®4£®1 Geographic and Geologic Setting 5£®4£®2 Theoretical Modeling of Rainfall-Induced Shallow Landslides 5£®4£®3 Laboratory Model Testing of Rainfall-Induced Landslides 5£®4£®4 Verification of the Infiltration Analysis Model 5£®4£®5 Comparative Analysis of the Shallow Landslide Model 5£®4£®6 Conclusions References 6 Slope Stability Analysis Based on Coupled Approach 6£®1 Introduction 6£®2 Hydromechanical Process of Soil Slope Under Rainfall 6£®2£®1 Equations Governing Coupled Infiltration and Deformation 6£®2£®2 The Limit Equilibrium Method for Stability of an Infinite Soil Slope 6£®2£®3 Analytical Solutions to Rainfall Infiltration in an Infinite Slope 6£®2£®4 Examples and Results 6£®2£®5 Conclusions 6£®3 Hydromechanical Coupling of Unsaturated Soil Slope Stability Due to Rainfall Patterns 6£®3£®1 Theory 6£®3£®2 Numerical Calculation of a Homogeneous Soil Slope 6£®3£®3 Conclusions 6£®4 Three-Phase Coupling of Soil Slope Under Rainfall 6£®4£®1 The Coupled Model 6£®4£®2 Equilibrium Equation 6£®4£®3 Analysis of Unsaturated Soil Slope Stability 6£®4£®4 Case Studies 6£®4£®5 Conclusions Appendix References