Chapter
1.3 Overview of Underground Sensing and Monitoring
1.3.1 Current Technologies for Underground Environmental and Geotechnical Monitoring
1.3.2 Environmental Underground Sensing and Monitoring
1.3.2.2 Wireless Underground Sensors and Networks
1.3.3 Geotechnical Underground Sensing and Monitoring
Mines and Underground Spaces
Hybrid Other Applications
2 Acoustic, Electromagnetic and Optical Sensing and Monitoring Methods
2.1 Principles of Acoustic and Electromagnetic Sensing
2.1.1.1 Conventional Underground Measurement Methods
2.1.1.1.1 Physical Field Methods
2.1.1.1.2 Acoustic Methods
2.1.1.1.3 Electrical and Electromagnetic Wave Methods
2.1.1.2 Conventional Devices Used for Underground Measurements
2.1.2 Acoustical Measurement Methods-AMM
2.1.2.1 Direct Detection Method
2.1.2.2 Acoustic Emission (AE) and Acoustic Source Location (ASL) Method
2.1.2.3 Reflection Seismology
2.1.2.4 Acoustic-to-Seismic (A/S) Coupling
2.1.3 Electric and Electromagnetic Methods
2.1.3.1 Electrical Resistivity Surveys (ERS)
2.1.3.2 Electromagnetic Induction (EMI) Method
2.1.3.3 Ground-Penetrating Radar
2.1.4 Optical Sensing Technologies Used in Underground Measurement
2.1.4.1 Vibration Measurement
2.1.4.1.1 Principles of Fiber Optic Vibration Sensing
2.1.4.1.2 Distributed Sensing of Vibration
2.1.4.1.3 Remote Sensing With Laser Doppler Technology
2.1.4.2 Strain/Stress Measurement
2.1.4.2.1 FBG for Strain Sensing
2.1.4.2.2 BOTDR for Strain/Stress Sensing
2.1.4.3 Temperature Measurement
2.1.4.3.1 FBG for Temperature Sensing
2.1.4.3.2 Raman Scattering Based Fiber-Optic Temperature Sensing
2.1.4.5 Examples of Practical Applications of Optical Sensor Technologies in Underground Measurements
2.1.4.5.1 Earthquake Observation
2.1.4.5.2 Mineral Exploration
2.1.4.5.3 Underground Pipeline Monitoring
2.1.4.5.4 Geological Disaster Warning
2.1.4.5.5 Coal Mine Safety Monitoring
2.2 GPR Technologies for Underground Sensing
2.2.1 Introduction to Ground Penetrating Radar
2.2.2 Operating Mechanism of GPR
2.2.2.1 GPR Signal Propagation in Dielectric Materials
2.2.2.2 GPR Sensing Resolution
Frequency Independent Antenna
2.2.4 GPR Image Processing
2.2.4.1 Vibration Effect Correction
2.2.4.2 Radio-Frequency Interference Reduction
2.2.4.4 Feature Extraction
2.2.4.5 Statistical Analysis for Singular Feature Detection
Other GPR Design Technologies
3 Geotechnical Underground Sensing and Monitoring
3.2.1 Vibrating Wire (VW) Strain Gages
3.2.1.1 Operating Principle of VW Gages
3.2.1.2 Commercial Vibrating Wire Strain Gages
3.2.2.1 Operating Principle of Foil Gages
3.2.2.2 Commercial Foil Strain Gages
Self-Temperature Compensation
3.2.2.3 Surface Preparation for Foil Strain Gages
3.2.2.4 Bonding of Foil Strain Gages
3.2.2.5 Attaching Lead-wires and Protection of Foil Strain Gages
3.2.2.6 Wheatstone Bridge Circuit
3.2.2.7 Optimizing the Excitation of Foil Strain Gages
3.2.3 Fiber-Optic Strain Gages
3.2.4 Installation of Strain Gages
3.3.1 Electric Load Cells
3.3.2 Hydraulic Load Cells
3.3.3 Osterberg Load Cells
3.4.1 Monitoring of Piezometric Pressure
3.4.1.1 Pressure Terminology
3.4.1.2 Piezometric Measurements
3.4.1.3 Piezometric Pressure Transducers
3.4.1.4 Pneumatic Piezometers
3.4.1.5 Piezometric Time Lag
3.4.2 Monitoring of Total Stress (Total Earth Pressure)
3.5 Monitoring Deformation
3.5.2 Linear Potentiometers
3.5.4 Vibrating Wire Joint Meters
3.5.6 Probe Extensometers
3.5.7 Slope Extensometers
3.6.1 Measurement of Tilt
3.6.1.1 Electrolytic Tilt Sensors
3.6.1.2 Accelerometric Tilt Sensor
3.6.1.3 Vibrating Wire Tilt Sensors
3.6.1.4 MEMS Based Tilt Sensors
3.6.3.1 Traversing Inclinometers
3.6.3.2 In-place Inclinometers
3.6.3.3 Shape Accelerometer Arrays (SAA)
3.7.1 Sensors for Monitoring Vibration
3.7.1.4 Proximity Sensors
3.7.2 Installation of Geophones and Accelerometers
3.8 Common Measurement Errors
3.8.6 Bias (Systematic) Errors
3.8.7 Precision (Random) Errors
3.9.6 Precision (Repeatability)
4 Environmental Underground Sensing and Monitoring
4.2 Overview of Conventional and Transitional Environmental Sensors
4.3 Wireless Sensor Networks for Environmental Sensing Applications
4.3.1 Background and Current State-of-the-Art
4.3.2 Recent Advances in WSN Hardware Suitable for Underground Environmental Applications
4.4 Fundamentals of WSN Supporting Environmental Applications: Advances and Open Issues
4.4.1 Sensor Network Deployment
4.4.2 Virtual Sensor Networks
4.4.3 Reliable Sensor Data Collection
4.5 Wireless Sensor Networks for Long-Term Monitoring of Contaminated Sites
4.5.1 WSN for Underground Plume Monitoring
4.5.2 Integrating WSN to Transport Models
4.5.3 Network Optimization
4.6 Wireless Sensor Networks for Remediation of Sites Contaminated With Organic Wastes
4.7 Wireless Sensor Networks for Carbon Leakage
5 EM-Based Wireless Underground Sensor Networks
5.2 Soil as a Communication Media
5.3 Propagation in the Underground Channel
5.3.1 Two-Wave UG Channel Model
5.3.2 Three-Wave UG Channel Model
5.3.3 Impulse Response Analysis of the UG Channel
Metrics for Impulse Response Characterization
5.3.4 Testbed Design for Impulse Response Parameters Analysis
5.3.5 UG Channel Impulse Response Parameters
5.3.5.1 Impact of Soil Moisture Changes on Impulse Response
5.3.5.2 Impact of Soil Texture
5.3.5.3 Impact of Operation Frequency
5.3.6 Impulse Response Model Validation Through Experiments
5.4 Effects of Soil on Antenna and Channel Capacity
Resonant Frequency of the UG Antenna
Bandwidth of the UG Antenna
Energy Efficiency of FEC Codes
Modeling Cluster Size Distribution in WUSN
Communication Coverage Model
Energy Consumption Analysis
Routing Using Neighbor Node
A New Connectivity Approach
5.7 WUSN Testbeds and Experimental Results
5.7.2 Results of WUSN Experiments
Software-Defined Radio Experiments
6 Fiber-Optic Underground Sensor Networks
6.1 Distributed Fiber-Optic Strain Sensing for Monitoring Underground Structures - Tunnels Case Studies
6.1.2 Distributed Fiber-Optic Sensing (DFOS) Based on Brillouin Scattering
Temperature Compensated Strain
Thermal Expansion of Concrete
6.1.3 Case Study 1: Monitoring of a Sprayed Concrete Tunnel Lining at the Crossrail Liverpool Street Station
Distributed Fiber-Optic Strain Sensor Installation
Monitoring Regime and Data Analysis
6.1.4 Case Study 2: Liverpool Street Station - Royal Mail Tunnel
Distributed Fiber-Optic Strain Sensor Installation
Results and Discussion: Cross-Sectional Behavior
Results and Discussion: Longitudinal Behavior
6.1.5 Case Study 3: Monitoring of CERN Tunnels
Project Background & Aim of Monitoring
Installation of Fiber-Optic Sensors & Planned Monitoring Scheme
Conclusions & Future Work
6.2 Fiber-Optic Sensor Networks: Environmental Applications
6.2.2 Fiber-Optic Devices for Sensing
6.2.3 Environmental Applications of FOS
6.2.3.1 FOS for Gas and Emission Sensing
6.2.3.1.1 Fiber-Optic Coated With ITO and Polyaniline Using Plasmon Resonance for Monitoring Ammonia Gas
6.2.3.1.2 Fiber-Optic Coated With Graphene Film Using Reflectivity for Monitoring Acetone Gas
6.2.3.1.3 Fiber-Optic Heterocore Coated With Thin Film of Au-Pd for Monitoring Hydrogen Gas
6.2.3.1.4 Fiber-Optic Coated With Au/SiO2 for Monitoring Ambient Gases in Atmosphere
6.2.3.1.5 Fiber-Optic Using Resonance Enhanced Multiphoton Ionization for Monitoring Volatile Organic Pollutants
6.2.3.1.6 Fiber-Enhanced Raman Multigas Spectroscopy for Monitoring Atmospheric Gases
6.2.3.1.7 Fiber-Optic Transmission Near-Infrared Spectroscopy for Monitoring Resin Curing and Humidity Ingress
6.2.3.1.8 Fiber-Optic Using Optical Remote Sensing of Flare Emissions
6.2.3.2 FOS for Water Contamination Sensing
6.2.3.2.1 Fiber-Optic Using Fourier Transform Infrared Spectroscopy-Attenuated Total Reflectance and Near-Infrared for Monitoring Chlorinated Hydrocarbons in Water
6.2.3.2.2 Fiber-Optic Using Evanescent Wave for Monitoring Nitrite in Water
6.2.3.2.3 Fiber-Optic Using UV for Monitoring COD and BOD in Water
6.2.3.2.4 Aptamer-Based Evanescent Wave Fiber Optic Bio-Sensor for Detection of Bisphenol-A in Water
6.2.3.2.5 Fiber-Optic With a Bragg Grating for Monitoring pH in Water
6.2.3.2.6 Fiber-Optic Using Optical Time Domain Reflectometry for Monitoring pH in Solution
6.2.3.2.7 Fiber-Optic Using Hetero-Core Fiber Coated With an Acrylic Polymer Doped with Prussian Blue for Monitoring pH in Solution
6.2.3.3 FOS For Soil Indices and Soil Contamination Sensing
6.2.3.3.1 Fiber-Optic Using BOTDR for Monitoring Water Content in Soil
6.2.3.3.2 Fiber-Optic Using Fluorescent Coating for Monitoring the Fuel Leaks
6.2.3.3.3 Fiber-Optic Using Synchronous Scanning Luminoscope for Monitoring Contaminated Soil and Ground Water
6.2.3.3.4 Fiber-Optic With Open-Path Fourier Transform Infrared Spectroscopy Monitoring Remediation of Polluted Sites
6.2.3.4 Mapping With Array-Based Distributed Fiber-Optic Sensors
6.2.4 General Conclusions
7 Advances and Challenges in Underground Sensing
7.1 Wireless Signal Networks for Global Underground Sensing
7.1.2 Wireless Signal Networks
7.1.2.1 Concept of Wireless Signal Networks
7.1.2.2 Subsurface Monitoring Applications
7.1.2.3 Subsurface Monitoring of WSiNs
7.1.3 Deployment Challenges of WSiNs
7.1.3.1 Installation and Management
7.1.3.2 Underground Radio Propagation and Communication Distance
7.1.4 Subsurface Event Detection and Classification
7.1.4.1 Event Detection and Window Selection
7.1.4.2 Event Classification on Selected Window
7.1.5 Evaluations of Wireless Signal Networks
7.1.5.1 Experiments of Subsurface Event Detection
7.1.5.1.1 Evaluation of Water Intrusion Detection
7.1.5.1.2 Evaluation of Relative Density Change Detection
7.1.5.1.3 Evaluation of Relative Motion Detection
7.1.5.2 Experiments of Subsurface Event Classification
7.1.5.2.1 Reference Data Generation
7.1.5.2.2 Event Classification of Water Leakage Experiment
7.2 Magneto-Inductive Tracking in Underground Environments
7.2.1.1 Approaches to GPS-Denied Tracking
7.2.1.2 Magneto Inductive Technology
7.2.3 Single Hop Localization
7.2.4 Multihop Localization
Bearing Versor Likelihood
Joint Log-Likelihood Maximization
7.2.5 Applications of Underground MI positioning
7.2.5.1 Iteratively Deployable Positioning Architecture
7.2.5.2 Revealing Underground Animal Behavior
7.2.6 Challenges and Limitations
7.2.6.2 Distortion Due to Nearby Conducting Objects
7.3 Integration of UAVs With Underground Sensing: Systems and Applications
7.3.1 Use Cases and Requirements
7.3.2 Communication-Aware Pairing Between UAVs and Underground Sensing Systems
7.3.3 Example: Dam Monitoring and Information System
8 Underground Sensing Strategies for the Health Assessment of Buried Pipelines
8.2 Overview of Buried Pipeline Sensing Technology
8.3 System Architecture and Design
8.3.6 Permanent Ground Displacement Simulation
8.4 Buried Wireless Sensing of Pipeline Behavior During PGD
8.4.1 Performance of Wireless Telemetry Underground
8.5 Assessment of Pipeline Responses and Damage
8.5.2 Joint Rotation and Translation
8.5.3 Pipe Strain Responses
8.5.4 Direct Joint Damage Sensing - Conductive Surface Sensors
8.5.5 Direct Joint Damage Sensing - Acoustic Emission
9 Outlook: Advanced Hybrid Sensing for Preemptive Response
9.2 Fiber-Optic (FO) Underground Sensor Networks
9.2.1 Fiber-Optic Chemical Sensors for Underground Measurements
(i) Absorbance-Based Techniques
(ii) Reflectance-Based Techniques
(iii) Fluorescence-Based Techniques
(iv) Surface Plasmon Resonance-Based Techniques
9.2.2 Distributed Fiber-Optic Sensors for Underground Sensing
(i) Stimulated Brillouin Scattering (SBS)
(ii) Brillouin Optical Time Domain Analysis (BOTDA)
(iii) Brillouin Optical Frequency Domain Analysis (BOFDA)
(iv) Brillouin Time Domain Reflectometry (BOTDR)
(v) Raman Optical Time Domain Reflectometry (ROTDR)
9.2.2.1 Infrastructure Health Measurements
(i) Deformation of Secant Pile Wall
(ii) Detection of Structural Cracks
(iii) Measurement of Strain Profiles on Structural Components
(iv) Measurement Of Leakage on Oil/Gas Pipelines
9.2.2.2 Dynamic Strains and impact Wave Measurements in Soil
9.2.2.3 Under Water Measurements
(ii) Water Column and Streambed
9.2.2.4 Safety and Security Applications
(i) Detection of Intrusion or Disturbance Underground
(ii) Detection of Methane in Underground Coal Mine
(iii) Detection of Stray Current in Coal Mine
(iv) Detection of Strain and Temperature in Nuclear Waste Repositories
9.3 Future Research on Advanced Hybrid Sensing for Preemptive Response
9.3.1 Crowdsensing for Preemptive Response to Underground Events
9.3.2 Pipeline Monitoring With Hybrid Sensing Using WSiN, GPR, and Crowdsensing
(i) Wireless signal networks (WSiN)
(ii) Low-Frequency Radio for Field-Scale Wireless Signal Networks
9.3.3 Land-Mine Detection Using Hybrid EM and Seismic-Acoustic Sensing
Underground Sensing
：Monitoring and Hazard Detection for Environment and Infrastructure
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