Landslide Disaster Mitigation in Three Gorges Reservoir, China

Foreword

Preface

Contents

Contributors

Top-Author Biographies

Introduction: The Scenary of Three Gorges, from Downstream to Upstream

Part I Regional Properties of Landslides

1 Geo-hazard Initiation and Assessment in the Three Gorges Reservoir

Introduction

Regional Assessments of Geo-hazards

Problems and Concepts

Basic Problems

Basic Concepts

Evaluation Method for Geological Hazards Regional Analysis

''Distribution Degree'' of Geological Hazards

''Potentiality Degree'' of Geological Hazards

''Dangerous Degree'' of Geological Hazards

''Harmful Degree'' of Geological Hazards

The Division Methods of Geological Hazard Evaluation

Evaluation of Geological Disasters in the Three Gorges Reservoir Area

Overall Features of Geological Disasters

Calculation and Analysis of Assessment

Disaster Prevention Measures

Initiation Mechanism of Complex Slope in the Three Gorges

Facts and Viewpoints

Basic Facts

Scientific Knowledge

Regional Geological Evidence

Regional Geological Structure

Neo-tectonic Stress Field in the Three Gorges Region Inversed Analysized by River System

River System Fractal Character

Supergene Dynamic Phenomenon

Ancient Chuanjiang River Connected with Ancient Xiajiang River Forming a Unified Yangtze River and Slope Evolution

The Ancient Chuanjiang River and the Xiajiang River Linking up Was a Great Natural Event

Geological Dynamic Background

The Complex Slope Failure Initiation and Assessment in Badong County

Statement of Problem

Geological Characteristic of Badong Big Slope

Morphologic Features

Stratum Combination

The Vestige of Geological Structure

The Question About the ''Badong Fracture''

Joint and ''Fracture'' of Slope Area

Geomechanics Model of Superficial Deformation and Damage

Badong Complex Slope System and Its Failure Initiation

Badong Complex Slope System

Initiation Theory of Gravity

Numerical Simulation Analysis with FLAC 3D

Regional Geo-environment Quality Assessment of the Badong Slope

Basic Idea

Geo-environment Evaluation of Badong Slope

Conclusions

References

2 Bank Slope Stability Evaluation for the Purpose of Three Gorges Reservoir Dam Construction 0

Types of Reservoir Bank Slopes and Assessment of the Stability Conditions

Types and Characteristics of the Reservoir Bank Slopes

Assessment on Stable Conditions of the Reservoir Bank Slopes

Rock Falls, Landslides, and Dangerous Rocks

Distribution Features of the Landslides

Geographical Distribution

Elevation of the Landslides Distribution

Relationship with the Lithology and Stratigraphy

Relationship with Geological Structure

Relationship with the Structure of the River Bank Slope

Structural Characteristics of the Landslides

Physical and Mechanical Properties of the Sliding Zone

Material Composition of the Sliding Zone

Physical and Mechanical Properties

Microstructure Feathers of the Sliding Zone

Hydro-geological Characteristics of the Landslides

Water-Bearing Capacity and Permeability of the Landslides

Recharge and Discharge Conditions of Ground Water in the Landslides

Ground Water Fluctuation and Its Affecting Factors

Formation Age of the Landslides

Determination of the Absolute Age for the Soil in the Sliding Zone

Referring to the Terraces of Yangtze River Valley

Stability Assessment of the Sliding Masses

Micro-geologic Judgment

Calculation by Limit Equilibrium Methods

Failure Probability Analysis

Sensitivity Analysis

Fuzzy Comprehensive Evaluation

Effect on the Rock Falls and Landslide by the Reservoir Impounding

Effect of the Normal Water Level

Effect of the Reservoir Water Level Fluctuation

Hazard Assessment for Failure of the Reservoir Bank Slopes

Analysis of the Main Factors Inducing Hazards

Estimation of the Size Sliding into River

Estimation of the Surge

Analysis and Assessment for Potential Harm

Influence on Storage Capacity and Lifespan of the Reservoir

Influence on Construction and Operation of the Key Structures

Influence on Navigation

Effects to Towns and Immigrant Settlement in the Reservoir Area

Monitoring, Prediction, and Mitigation for the Main Landslides

Deformation Monitoring and Prediction for the Main Landslides

Ground Deformation Monitoring

Deep Deformation Monitoring

Prediction

Treatment of the Landslides

Water Drainage

Unloading

Anchoring and Retaining

3 Research on the Characteristics and Slope Deformation Regularity of the Badong Formation in the Three Gorges Reservoir Area

Introduction

Development Characteristics and Space Variation of the Strata of the Badong Formation in the Three Gorge Reservoir Area

The Lithology and Space Variation of Lithology Combinations of the Strata of the Badong Formation

Space Variation of Stratum Thickness of Badong Formation

Characteristics of Structural Deformation of Badong Formation

Cleavage

Joint

Geological and Construction Property of the Rock Mass Structure in the Badong Formation

Property of Rock Mass Structure

Physical--Mechanical Property of the Soft Layer

Engineering Properties of the Rock Mass

Physical--Mechanical Property of the Rock Mass

Mechanical Properties of the Structural Plane

Estimation of Mechanical Parameters of Rock Masses

Recommended Parametric Values for Mechanical Calculation of Rock Mass

Typical Landslide of the Badong Formation Deformation Mode of the Huangtupo Landslide

Geological Background

Long-Term Deformation of the Slope

Landslide

Subsequent Reform of Landslide

Landslide Evolution Pattern

Conclusions

References

4 Distribution of Dangerous Rockmasses on the High Steep Slopes in the Three Gorges Area

Introduction

Geological Background for High Steep Bank Slopes and Dangerous Rockmasses in the Three Gorges River Valley

Basic Features of Rock and Soil

Basic Features of the Weak Structural Plane of Rock and Soil

Features of Rockmass Structural Plane

Distribution Features of Dangerous Rockmasses in the Three Gorges Reservoir Area

Profiles of Dangerous Rockmasses

Description of the Key Dangerous Rockmass

Fengxiangxia Dangerous Rockmass in Qutang Gorge

Hengshixi Dangerous Rockmass in Wu Gorge

Tongxincun Dangerous Rockmass in Wangxia Village, Wu Gorges

Liaojiaping Dangerous Rockmass in Wangxia Village, Wu Gorge

Jianchuandong Dangerous Rockmass in Wu Gorge

Jiandaofeng Rockfall in Wu Gorge

Huangyanwo Dangerous Rockmass in Wu Gorge

Shangpingtuo Landslide and Houzibao Dangerous Rockmass in the Front of Wu Gorge

Suozishan Dangerous Rockmass in Xiling Gorge

Baituo Dangerous Rockmass in Xiling Gorge

The Wentianjian Dangerous Rockmass in Xiling Gorge

The Jiuwanxi Dangerous Rockmass at the Entrance of Jiuwanxi Brook, Xiling Gorge

Conclusions

References

5 An Evaluation Study of Bank Collapse Prediction in the Three Gorges Reservoir Area

Introduction

Bank Collapse Types in the Three Gorges Reservoir Area

Wash and Abrasion

Toe-Erosion Collapse

Rock Break-Off and Slides

Landslide

The Prediction Parameter in Three Gorges Reservoir Area

Eigenvalue of the Bank Collapse Prediction Parameter

Sampling Investigation of Bank Collapse Prediction Parameter

Statistics of the Eigenvalue of Bank Collapse Prediction Parameter in the Three Gorges Reservoir Area

Bank Collapse Prediction Parameter of the Alluvial--Proluvial Bank Slope

Bank Collapse Prediction Parameter of the Residual Soil Slope and Landslide Accumulation Slope

Bank Collapse Prediction Parameter of the Wushan Loess-Like Soil and the Intensely Whole Weathered Granite Belt

Bank Collapse Prediction Parameter of Redbed Slope

Evaluation of Bank Collapse Predictions in the Three Gorges Reservoir Area

Classified Illustration in Terms of BSSPM

Illustration of Wash--Abrasion and Toe-Erosion Collapse

Bank Collapse Prediction of Landslide

Attention Points on the Application of BSSPM

Application of BSSPM

Application of BSSPM in the Analogical Prediction of Reservoir Bank Collapse

The Application of BSSPM to the Bank Collapse Prediction in Three Gorges Reservoir Area

Conclusions

References

6 Distribution Features of Landslides in Three Gorges Area and the Contribution of Basic Factors

Distribution Features of Landslides

Landslides and Lithology

Landslides and Environment

Landslides and Landforms

Characteristics of Landslide Hazards

Root Factors of Landslides

Inversion of Root Factors

Determining the Root Factors of Landslides

Statistics of Environmental Root Factors

The Contribution Rates of Root Factors to Landslides

Contribution Index

Contribution Rate

The Contribution Rates of Strata

The Contribution of the Stratas Areas

The Contribution to the Number of Landslides

The Contribution to the Scales of Landslides

Calculating the Contribution Rates

Giving Values

Superimposing Counting

Analysis of Contribution Rates

The Contributions of Height Differences

The Contribution Rate of Slope Shape

The Contribution Rate of Slope Grade

The Contribution Rate of Aspect

Comprehensive Evaluations and Weights of the Root Factors Contribution Rates

Evaluations of Contribution Rates

The Switch of Contribution Rate and Weight

References

7 Discussion on Land Use Based on Landslide Management in Three Gorges Reservoir Areas

Introduction

The Effect of the Landslide Disasters on the Three Gorges Reservoir Areas

The Historical Landslide Management Situations

The Present Growth of the Geographic Disaster Areas in Zigui County

The Forced Conversion of Land-Use Types

Research on the Development and Utilization of the Land Destroyed in the Landslide Disasters

Engineering Technical Methods for the Land Treatment

Example of Analysis: Treatment, Development, and Utilization of Land in Xintan Which Was Destroyed in the Landslide

Research on the Mode

Conclusions

References

Part II Case Studies for Typical Landslides

8 Mechanism for the Rapid Motion of the Reactivated Qianjiangping Landslide in Three Gorges Dam Reservoir, China

Introduction

Features of the Landslide

Scratches on the Failure Surface

Possible Triggering Factors and Sliding Mechanism

Experimental Study on the Rapid Sliding Mechanism of the Reactivated Landslide

Sampling the Sliding Planes

Soil Properties

Ring Shear Tests to Simulate the Sliding Process

Shear Torque Test to Simulate the Sliding Process

Shear Velocity-Controlling Test to Simulate the Sliding Process

Discussion and Conclusions

References

9 Evaluation of the Roles of Reservoir Impoundment and Rainfall for the Qianjiangping Landslide in Zigui County,Three Gorges Area

Introduction

Site Description

Analysis Methods

Results and Discussion

Sensitivity of the FS to the Parameters Within the Reservoir Impoundment and Rainfall

Quantitative Roles of the Reservoir Impoundment and Rainfall in Occurrence of the Landslide

Conclusions

References

10 Unsaturated Creep Test and Modeling of Soils from the Sliding Zone of the Qianjiangping Landslide in the Three Gorges Area, China

Introduction

Unsaturated Soil Creep Apparatus

Design Concept

The Structure of the Unsaturated Soil Creep Apparatus

Testing Method

Some Important Items That Need Attention

Unsaturated Creep Test of Slip Soils in the Qianjiangping Landslide

Test Soil Samples

Unsaturated Soil Shear Creep Loading Test

Test Procedure

Creep Test Result

Unsaturated Creep Modeling of Slip Soils in the Qianjiangping Landslide

Modeling Concept

Creep Strain--Time Relation

Creep Strain--Stress Relation

Creep Strain--Time--Stress Relation

Determination of the Model Parameters

Model Verification

Conclusions

References

11 Monitoring on Shuping Landslide in the Three Gorges Dam Reservoir, China

Introduction

Description of the Shuping Landslide

Landslide Geometry

Extensometers Monitoring Results

Part 1: August 2004--July 2006

Part 2: August 2006--July 2007

Part 3: August 2007--May 2007

Longitudinal Deformation Model

Conclusions

References

12 The Anlesi Landslide in Wanzhou, China: Characteristics and Mechanism of a Gentle Dip Landslide

Introduction

Geological Backgrounds

Characteristics of Anlesi Landslide

Macroscopic Geological Features of Slip Zones

The Mineral Components of the Slip Zones of the Anlesi Landslide

X-Ray Diffraction Analysis

Infrared Ray Analysis

The Microcosmic Structure Features of Slip Zone

Features of Striations

Features of Mineral Directional Crystal Structure

Physical Properties of Slip Zones

Grain Size

Maximum Dry Density and Optimum Water Content

Liquid and Plastic Limit

Swelling Potential

Shear Strengths

Factors Contributing to the Gentle Dip Landslides

Incompetent Beds

Distribution of Incompetent Beds

Fabric and Structure of Incompetent Beds

Shear Strength of Incompetent Beds

Contributions of Incompetent Beds to Landslide Formation

Latest Tectonic Activities

Intensive Rainfall

Creep Properties of the Slip Zones of the Anlesi Landslide

Test Facilities

Test Procedure

Test Results

Burgers Rheological Model of Slip Zone Soils

The Burgers Model Parameters

The Nonlinear Burgers Model

Numerical Simulation of the Anlesi Landslide

Geological Model

Meshes for Numerical Modeling

Numerical Simulation Considering the Elastic--Plastic Properties of Rock and Soil

Numerical Simulation Considering the Rheological Properties of Rock and Soil

Conclusions

References

13 Preliminary Study on Mud-Rock Flows Channel of the Bailuxi River, Wuxi County, China

Introduction

Physical Geography, Geology and Geomorphology Background

Physical Geography

Geomorphology

Lithology

Tectonics

Vegetation, Cultivation and Human Activity

Distribution and Growth Features of Mud-Rock Flow

Analysis of the Yangjiawan Branch Channel Mud-Rock Flow

The Mud-Rock Flow of the Yangjiawan Branch Channel

Formation Area of Yangjiawan Branch Channel Mud-Rock Flow

The Movement and Accumulation Region of the Yangjiawan River Channel Mud-Rock Flow

Evaluation of the Probability of a Yangjiawan Branch Channel Mud-Rock Flow

Analysis on the Possibility for the Bailuxi Main Channel to Burst into a Mud-Rock Flow

Hazard Analysis of the Bailuxi River Mud-Rock Flow and the Resulting Countermeasures

Reference

14 Stability Assessment and Stabilizing Approaches for the Majiagou Landslide, Undergoing the Effects of Water Level Fluctuation in the Three Gorges Reservoir Area

Introduction

Engineering Geologic Characteristics of the Majiagou Landslide

The Geologic Background of the Landslide

The Geomorphic Form of the Landslide

The Material Components of the Landslide

The Hydrogeological Characteristics of the Landslide

Physical and Mechanical Properties of the Soil of the Landslide

Density of the Slide Mass

Shear Strength of the Slide Zone

Permeability of the Soils of the Landslide

Effect on the Ground Water by the Reservoir Water Level Fluctuation

Stability Assessment of the Landslide Undergoing the Reservoir Water Level Change

Stabilizing Work and the Efficiency

Conclusions

References

15 Mass Rock Creep and Landsliding on the Huangtupo Slope in the Reservoir Area of the Three Gorges Project, Yangtze River, China

Introduction

Geological Setting

Mass Rock Creep

Brief Introduction of Mass Rock Creep

Mass Rock Creep at Huangtupo

Toppling

Deep-Seated Creep

Landslide at Huangtupo

Landform

Surface Geological Texture

Sliding Zone

Electrical Resistivity Constraints for Landslide Geometry

Shallow Process on the Surface of the Preexisting Huangtupo Landslide

Summary and Discussion

Conclusion

References

16 Study on the Possible Failure Mode and Mechanism of the Xietan Landslide When Exposed to Water Level Fluctuation

Introduction

Introduction to the Xietan Landslide

Fluctuation of Reservoir Water Level

Physical Model Test

Apparatus for the Model Test

Section Plane Selection for the Model Test

Preparation of Similarity Materials for the Model Test

Formulation of Similarity Material of the Model Test

Simulation of Fluctuation of Reservoir Water Level

Model Test Phenomenon and Its Analysis

Failure Mode and Mechanism of the Landslide

Exploration of the Failure Modes of Other Landslides Similar to the Landslide

References

17 A Study of the 1985 Xintan Landslide in Xiling Gorge, Three Gorges Area, China

Introduction

Natural Settings and the Geological Structure of the Xintan Slope

Features and Mechanism of the Landslide

Developing Process of the Landslide

Upslope-Stepwise Progressive Deformation Stage (Before the Rainy Season of 1983)

Integral Pushing-Type Slide Stage (May 1983--Major Landsliding in 1985)

The Course of the Landslide

Scope and Magnitude of the Landslide

Mechanism and Causes of the Landslide

Mechanical Analysis of Jiangjiapo Landslide

Study of the Parameters of the Sliding Movements

Slide Seismogram Studies

Monitoring and Prediction of Landslide Activities

Slope Deformation Monitoring

Prediction of the Landslide Occurrence

Conclusions

References

18 Time Prediction of the Xintan Landslide in Xiling Gorge, the Yangtze River

Introduction

The Sliding Process

Characteristics of Landslide Movement

Deformation Features of the Landslide

The Features of Sliding Debris

Essential Features of the Landslide

Topography

Materials and Structure

Bedrock Structures

Hydro-geological Conditions

Boundary Conditions

Formation Mechanism of the Landslide

Mechanism of Destabilization

Falling Loading

The Effect of Precipitation

Landslide Monitoring and Prediction

Features of Deformation Monitoring

Progressing Development Features of the Landslide

Landslide Prediction

Deformation Features of Sliding Remains

Aspects of Successful Prediction for Failure of the Xintan Landslide

Conclusions

References

19 Back-Analysis of Water Waves Generated by the Xintan Landslide

Introduction

Engineering Geology of the Xintan Landslide

Topography and Geomorphology of Xintan Landslide

Rock and Soil of the Xintan Landslide

Calculations of Landslide Velocity and Water Wave

Calculation of Landslide Velocity

Calculation of the Initial Water Wave Characteristics Generated by the Landslide

Calculation of the Propagation of Water Wave

Calculation of the Run-up of the Wave

Back-Analysis of Water Waves Generated by the Xintan Landslide

The Shear Strength Parameters of the Sliding Zone of the Xintan Landslide

Back-Analysis of the Internal Friction Angle of the Sliding Zone in a State of Movement

Conclusions

References

Part III New Methodologies Applied in this Area

20 Intelligent Optimization of Reinforcement Design Using Evolutionary Artificial Neural Network for the Muzishu Landslide Based on GIS

Introduction

Integration Method for Optimization of Landslide Reinforcement Design

Evolutionary Artificial Neural Network

Construction of Nonlinear Relationship Between Reinforcement Parameters, Factor of Safety and Engineering Cost

Search of Optimal Reinforcement Parameters Using Genetic Algorithm in Global Space

Three-Dimensional Visualization and Subsidiary Analysis for Strata Information and Reinforcement Design Based on GIS Technique

Intelligent Optimization of Reinforcement Design for the Muzishu Landslide

Brief Description of the Muzishu Landslide

Reinforcement Design and Optimization Procedure

Three-Dimensional Visualization and Subsidiary Analysis for Reinforcement Design

Discussion and Conclusions

References

21 The Application of Fractal Dimensions of Landslide Boundary Trace for Evaluation of Slope Instability

Introduction

Features of Landslides in the Study Area

Methodology

Results and Discussion

Fractal Dimensions of Landslides

Relationship Between Fractal Dimensions and Slope Instability

Qualitative Analysis of the Relationship Between Landslide Boundary Traces and Slope Instability

Quantitative Description for Slope Instability Using Fractal Dimensions of Landslide Boundary Traces

Conclusions and Remarks

References

22 Uncertainty Evaluation of the Stability of the Huanglashi Landslide in the Three Gorges of the Yangtze River

Introduction

Characters and Geological Environment of the Huanglashi Landslide

General Characters of the Landslide

Character of the Hengping Landslide

Character of the Dashiban Landslide

Character of the Taizijiao Landslide

Geological and Environmental Characters

Deformation and Failure Mechanism of the Landslide

The Hengping Landslide

The Dashiban Landslide

Taizijiao Landslide

Uncertainty Analysis on the Stability of the Huanglashi Landslide

Uncertainty Analysis on the Stability of the Hengping Landslide

Determination of Safety Coefficient

Uncertainty Analysis of the Hengping Landslide

Preliminary Elevation of the Stability of the Hengping Landslide

Analysis of the Stability of the Dashiban Landslide

Character of Deformation Development

The Probable Location of Shear Outlets

Analysis on the Stability of the Dashiban Landslide

The Effect of the Dashiban Landslide Failure on the Hengping Landslide

Analysis on the Stability of the Taizijiao Landslide

Conclusions

References

23 Recognition of Lithology and Its Use in Identification of Landslide-Prone Areas Using Remote Sensing Data

Introduction

The Study Area

Recognition of Lithology Using Remote Sensing Data

Preparation of Remote Sensing Data

Interpretation of Lithology Units Using Remote Sensing Images

Analysis of the Lithostratigraphic Factor in Landslide Hazard Zonation

Results and Discussions

References

24 Construction and Application of a Real-Time Monitoring System for Landslides

Introduction

Signification and Characteristic of Real-Time Monitoring

System Structure

Data Collection System

Data Transmission System

Information Processing and Distribution System

Key Technologies and Solutions

Acquisition System and the Automatic Convergence of the Transmission System

Servo Data Processing and Storage Procedures

Data File Names Agreement

Application and Evaluation

Monitoring Method and Monitoring Instruments

Management

Demonstrative Station Data Collection System

GPRS Remote Wireless Transmission System

Demonstrative Station Information Issuance System

Bottom Database System

Information Issue Homepage

Assessment

Conclusion

References

25 Entropy-Based Hazard Degree Assessment for Typical Landslides in the Three Gorges Area, China

Introduction

Method

Index Selection

Data Standardization

Entropy Calculations

Weights of Index

Model

Application

The Study Area

Data and Index Selection

Model Established

Hazard Assessment

Discussion

Conclusion

References

26 The Conceptual Model of Groundwater Systems in a Large-Scale Landslide -- A Case Study of the Baota Landslide in the Impoundment Area of Three Gorges Project

Introduction

The Characteristics and the Conceptual Model of the Groundwater Systems of the Landslide

Geological Setting and Hydro-geological Structure

The Flow Field and the Regime of the Groundwater Systems

The Chemical Characteristics and Temperature Fields of the Groundwater Systems in the Landslide

The Environmental Isotopes of the Groundwater

Conclusion and Discussion

References

27 Bank Collapse Along the Three Gorges Reservoir and the Application of Time-Dependent Modeling

Introduction

Modeling Test Design and Procedure

Mono-factor Model Test

Multi-factor Model Test

Design and Procedure of the Multi-factor Model Test

Model Test in Different Types of Bank Collapse

Sensitivity Analysis for Effect Factors

Time-Dependent Model Test

Design Procedure of the Time-Dependent Model Test

Test Results and Analysis

Analysis of Bank Collapse Development Process

General Process of Bank Collapse

Evidence of Bank Collapse Termination

Conclusion

References

Appendix A: Stratigraphic Column in the Three Gorges Area(Modified from Yin 2007)

Appendix B: Distribution of main landslides in the Three GorgesReservoir