Contents
1 Introduction 1
1.1 Background 1
1.1.1 Landslide 1
1.1.2 Earthquake-Induced Landslides 2
1.2 Preventive Countermeasures and Two Major Issues 5
1.3 Scope and Objectives 5
1.4 Monograph Organization 8
References 9
2 Review of Studies on Earthquake-Induced Landslides 11
2.1 Introduction 11
2.2 Seismic Slope Stability Analysis 12
2.2.1 Pseudo-Static Methods 13
2.2.2 Dynamic Sliding Block Methods 17
2.2.3 Stress-Strain Methods 22
2.3 Landslide Run-Out Analysis 24
2.3.1 Experiment Methods 24
2.3.2 Empirical Methods 25
2.3.3 Analytical Methods 27
2.3.4 Numerical Simulation Methods 28
2.4 Comparisons of Various Methods and Conclusions 30
References 31
3 Seismic Slope Stability Analysis by Considering Tension Crack 41
3.1 Introduction 41
3.2 Numerical Simulation Method 44
3.2.1 Failure Mechanism in the FLAC3D 44
3.2.2 Dynamic Formulation 47
3.2.3 Results 52
3.2.4 Discussions 54
3.3 Comparison of Limit Analysis and Numerical Simulation 59
3.3.1 Comparison of the Depth of Tension Failure 59
3.3.2 Comparison of FOS 59
3.3.3 Comparison of the Shape of Slip Surface 60
3.4 Conclusions 60
References 61
4 Run-Out Analysis of Earthquake-Induced Landslides 63
4.1 Introduction 63
4.2 Trampoline Effect Induced by Extreme Seismic Loadings 71
4.2.1 Extreme Seismic Loading 71
4.2.2 Trampoline Effect 73
4.2.3 Verification of Trampoline Effect Using DDA 75
4.3 Existing Long Run-Out Models 76
4.3.1 Fluidizations 77
4.3.2 Air Cushion 77
4.3.3 Liquefaction 78
4.4 Multiplex Acceleration Model (MAM) and Extension 78
4.4.1 Single Sliding Model 79
4.4.2 Multi-movement Model 81
References 84
5 Extension of Discontinuous Deformation Analysis
and Application in Run-Out Analysis of Earthquake-Induced
Landslides 87
5.1 Introduction 87
5.2 Theory of DDA 89
5.2.1 Basic Theory and Time Discretization 89
5.2.2 Contact Mechanism 91
5.3 Validation of Static Sliding 94
5.3.1 Limitation of the Original DDA 94
5.3.2 Extension of the Original DDA by Importing Edge-to-
Edge Contact 100
5.3.3 Validation of Static Sliding Block 103
5.3.4 Remarks 107
5.4 Validation of Dynamic Block Model 109
5.4.1 Effects of Model Types on the Residual Displacement 110
5.4.2 Effects of Vertical Seismic Force on the Residual
Displacement 113
5.4.3 Effects of Model Strike Direction on the Residual
Displacement 115
5.4.4 Remarks 116
5.5 Validation of Trampoline Effects 116
5.6 Simulation of the Donghekou Landslide by Using
the Developed DDA Program 118
5.6.1 DDA Model, Parameters, and Seismic Loadings 119
5.6.2 Results of DDA Simulation 119
5.7 Conclusions 122
References 122
6 A Case Study of Earthquake-Induced Landslide 125
6.1 Introduction 125
6.2 Background Information 127
6.2.1 The Wenchuan Earthquake 127
6.2.2 The Daguangbao Landslide 128
6.3 Material Properties and Ground Motion 134
6.3.1 Material Properties 134
6.3.2 Ground Motion 136
6.4 Stability Analysis by the FLAC3D 141
6.4.1 The Finite Difference Method 141
6.4.2 FOS and Strength Reduction Technique 144
6.4.3 Numerical Simulations 144
6.4.4 Results and Discussions of the Stability Analysis 149
6.5 Run-Out Analysis by the Extended DDA 152
6.5.1 The Seismic DDA Code and Basic Assumptions 152
6.5.2 Geometry and Properties of Sliding Blocks 156
6.5.3 Earthquake Forces 156
6.5.4 Results and Discussions of the Run-out Analysis 157
6.6 Conclusions 165
References 166
7 Conclusions and Future Studies 171
7.1 Conclusions 171
7.2 Future Studies 172
Appendix A 175
Appendix B 185
Bibliography 193