Emergency Handling of the "5. 12" Tangjiashan Barrier Lake

This book introduces emergency management of barrier lakes systematically, including theories and practices, risk assessment under extremely high-risk conditions, evolution of outburst floods, analysis of anti-impact stability, and emergency management technology and assessment of risk elimination effect. It takes the Tangjiashan barrier lake as a successful case study to illustrate effective treatment of barrier lake with high risks, poor environmental conditions, extremely urgent rescue time and high disposal difficulties. It retains a large number of images and data of great research value for the lake risk assessment and building technological emergency system. It provides a reliable reference for the government, scientific researchers and survey and design team to deal with the sudden natural disaster in barrier lakes, especially caused by huge earthquake. Preface Acknowledgements Contents About the Authors Abbreviations and Acronyms 1 Overview 1.1 Formation of Barrier Lake 1.2 Barrier Lake-Break 1.2.1 Study on the Forms of Barrier Lake-Break 1.2.2 Hazard Level of Barrier Lake-Break 1.2.3 Disaster Loss Assessment of Barrier Lake-Break 1.3 Theoretical and Experimental Study on Barrier Lake-Break 1.3.1 Theoretical Analysis 1.3.2 Hydraulic Test Study 1.3.3 Simulation of the Dam-Break Process of Earth-Rock Dam 1.3.4 Study on Simulation of Dam-Break Flood 1.4 Assessment of Hazard Level and Handling of Tangjiashan Barrier Lake References 2 Hydrological Analysis of Tangjiashan Barrier Lake Area 2.1 Basic Situation of the Affected Area 2.1.1 Basic Situation of Fujiang River Basin 2.1.2 Basic Situation of Tongkou River Basin 2.1.3 Design Flood of Fujiang River Main Stream 2.2 Hydrological Characteristics of Barrier Lake Area 2.2.1 Hydrological Overview of Barrier Lake Area 2.2.2 Design Flood 2.3 Acquisition and Application of Basic Data 2.3.1 Acquisition of Basic Data 2.3.2 Application of Acquired Data 2.4 Relation Between Water Regime and Emergency Handling Project 2.4.1 Relation Between Rainstorm and Flood in Barrier Lake Area 2.4.2 Relation Between Water Regime and Disaster Relief Construction Period 2.4.3 Water Regime Prediction of Barrier Lake Area During Construction Period Reference 3 Geological Characteristics of the Tangjiashan Barrier Lake Area 3.1 Geological Conditions of the Barrier Lake Area 3.1.1 Original Topography 3.1.2 Stratum Lithology 3.1.3 Geological Structure 3.1.4 Earthquake 3.2 Formation Conditions and Inversion of the Tangjiashan Landslide 3.2.1 Formation Conditions of the Tangjiashan Landslide 3.2.2 Formation Process Analysis of the Tangjiashan Barrier Dam 3.2.3 DDA Numerical Simulation of Barrier Dam Formation Process 3.3 Geological Characteristics of the Tangjiashan Barrier Dam 3.3.1 Barrier Dam Morphology 3.3.2 Barrier Material Composition 3.3.3 Physical and Mechanical Properties and Permeability of the Barrier Dam 3.4 Evaluation and Analysis of the Barrier Dam Stability 3.4.1 Geological Macroscopic Evaluation of the Barrier Dam Stability 3.4.2 Analysis of the Possibility of the Tangjiashan Barrier Dam Collapse 3.4.3 Analysis of the Collapse Process of the Tangjiashan Barrier Dam 3.4.4 Analysis of Barrier Dam Stability Calculation 3.5 Evaluation and Analysis of Discharge Channel Stability 3.5.1 Evaluation of Discharge Channel Stability 3.5.2 Stability Analysis of the Side Slope of the Discharge Channel 4 Analysis on Flood Evolution of Tangjiashan Barrier Lake Dam-Break 4.1 Analysis on Barrier Dam-Break Possibility and Scouring Form of Barrier Dam During the Emergency 4.1.1 Analysis on Scouring Resistance Capacity of Mixture Forming Barrier Dam 4.1.2 Analysis on Possibility of Abrupt Failure and Progressive Failure 4.2 Analysis on Discharge Capacity from Barrier Lake 4.2.1 Calculation Method 4.2.2 Calculation of Discharge Capacity from Barrier Lake 4.2.3 Calculation of Discharge Channel Flood Regulation 4.3 Calculation Analysis on Barrier Dam-Break Flood 4.3.1 Calculation Model for Barrier Dam-Break Flood 4.3.2 Calculation Analysis of First-Time Barrier Dam-Break Flood 4.3.3 Analysis of Secondary Barrier Dam-Break Flood 4.3.4 Related Understanding of Calculation Analysis on Barrier Dam-Break Flood 4.4 Calculation Analysis Pattern of Barrier Dam-Break Flood 4.4.1 Basic Data to Be Collected 4.4.2 Definite Solution Condition and Boundary Treatment 4.4.3 Preparation of Calculation Working Conditions and Results Analysis 4.4.4 Working Pattern for Calculating Barrier Dam-Break Flood of Tangjiashan Barrier Lake 4.4.5 Conclusion 5 Study on the Anti-Scouring Stability of Discontinuous Wide Graded Mixture of Barrier Dam 5.1 Study on the Barrier Dam-Break 5.1.1 Research Status of Barrier Dam-Break 5.1.2 Research Status of Incipient Motion and Scouring Characteristics of Wide Graded Mixture 5.2 Material Composition Analysis of Barrier Dam 5.3 Scouring Experiment for Wide Graded Mixture 5.3.1 Experimental Design 5.3.2 Criterion of Incipient Motion 5.3.3 Test Results and Analysis 5.4 Experimental Study on Barrier Dam-Break of Wide Graded Mixture 5.4.1 Experimental Design for Barrier Dam-Break Model 5.4.2 Experimental Study on Dam-Break Mode 5.4.3 Analysis of Dam-Break Peak Discharge and Mechanism 5.4.4 Conclusions References 6 Study on Emergency Handing Scheme of Tangjiashan Barrier Lake 6.1 Domestic and International Handing Technologies of Barrier Lake 6.2 Overall Emergency Handing Plan of Tangjiashan Barrier Lake 6.2.1 Necessity and Overall Objective for Emergency Handling 6.2.2 Basic Principles of Emergency Handling 6.2.3 The Overall Emergency Handling Plan 6.3 Emergency Engineering Plans of Tangjiashan Barrier Lake 6.3.1 Draining and Scouring Principle and Realization Way of Discharge Channel 6.3.2 Ideas and Principles of Design 6.3.3 Route Selection and Arrangement 6.3.4 Structure Design of Drainage Channel 6.4 Emergency Personnel Evacuation Plan of Tangjiashan Barrier Lake 6.4.1 Necessity of Personnel Evacuation to Avoid Danger 6.4.2 Emergency Personnel Evacuation Plan 6.5 Emergency Response Security Measures of Tangjiashan Barrier Lake 6.5.1 Rapid Decision-Making and Response Mechanism 6.5.2 Prediction and Forecasting System of Water and Precipitation 6.5.3 Remote Real-Time Video Monitoring System of the Barrier Dam 6.5.4 Safety Monitoring System in the Dam Area 6.5.5 Communication Security System 6.5.6 Expert Consultation and Decision-Making Mechanism of Collapse Prevention 6.6 Summary References 7 Construction of Emergency Handling of the “5.12” Tangjiashan Barrier Lake 7.1 The Organization and Implementation of Construction 7.1.1 Construction Features of Emergency Handling of the “5.12” Tangjiashan Barrier Lake 7.1.2 External Transportation Conditions 7.1.3 Construction Scheme and Optimization Measures During Implementation 7.1.4 Construction Progress and Construction Period 7.2 Dynamic Optimization and Adjustment of Discharge Channel 7.2.1 Dynamic Adjustment 7.2.2 Scheme of Excavating a New Branch Channel 7.2.3 Scheme of Blasting Method for Channel Excavation 7.2.4 Scheme of Channel Bottom Blasting and Deep Excavation 7.3 Risks in the Implementation of the Drainage Scheme and Countermeasures 7.3.1 Risks in the Implementation of the Drainage Scheme 7.3.2 Countermeasures for Engineering Risks 8 Emergency Monitoring and Guarantee System 8.1 Hydrologic Emergency Monitoring System 8.1.1 Purpose and Principles 8.1.2 Items of Monitoring and Monitoring Scheme 8.1.3 Emergency Survey on the Geometric Parameters and Typical Sections of the Barrier Lake 8.2 Information Transmission and Communication System 8.2.1 Emergency Communication Channel Selection 8.2.2 Network Structure of Emergency Monitoring and Reporting Data Transmission 8.3 Hydrological Information Analysis and Processing System 8.3.1 Difficulties in Monitoring Calculation and Analysis of Measured Hydrological Data Under Special Conditions 8.3.2 Difficulties in the Analysis and Processing of Measured Data 8.3.3 Compilation and Calculation Analysis of Measured Hydrological Data 8.4 Flow and Rain Forecast and Outburst Flood Warning System 8.4.1 Difficulties of Forecast 8.4.2 Numerical Precipitation Forecast Technology 8.4.3 Water Regime Forecast Scheme 8.4.4 Main Forecast Method 8.4.5 Hydrometeorological Forecast 8.5 Broadband Wireless Emergency Communication System 8.6 Summary 8.6.1 Hydrologic Emergency Monitoring System 8.6.2 Information Transmission and Communication System 8.6.3 Information Analysis and Processing System 8.6.4 Meteorological and Hydrological Forecast System 8.6.5 Extensive Application of Broadband Wireless Video 9 Water Discharge Process and Disaster Relief Effect Evaluation 9.1 Scouring Process in Discharge Channel 9.1.1 Retrogressively Scouring Process 9.1.2 Lateral Erosion Process 9.1.3 Deformation of Side Slope During Discharge 9.1.4 Effects of Engineering Measures 9.2 Barrier Lake Discharge Process and Back Analysis 9.2.1 Discharge Process of Barrier Lake 9.2.2 Barrier Lake Discharge Process and Back Analysis 9.2.3 Social and Economic Benefit of the Emergency Handling Measures 9.3 Initial Stability Assessment of the New River Channel 9.3.1 Remaining Barrier Dam Body on Left Bank 9.3.2 Slope Stability of the New River Channel 9.4 Flood Discharge Capacity of the New River Channel 9.4.1 Cross Section of the New River Channel and Hydraulic Calculation 9.4.2 Flood Regulation Calculation 9.5 A Summary of Experience Appendix Timeline of Key Events