Download PRIME: Proactive Infrastructure Monitoring and Evaluation

PRIME: Proactive Infrastructure Monitoring
and Evaluation
PRIME MOVERS:
Jon Chambers / Philip Meldrum / Paul Wilkinson
Geophysical Tomography Team
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PRIME –
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What is it ?
A new low cost – low power 4D [time lapse 3D] ground resistivity imaging system for
critical zone monitoring.
Develop a system and demonstrate the operational benefits of PRIME to potential
beneficiaries including the research community, asset owners and service providers……
Critical Zones
Geohazards
Landfill / Barriers
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Mining groundwater rebound
Groundwater
contamination
Electrical Resistivity Tomography (ERT) – What is it ?
NON-INVASIVE
• Resistivity – the resistance of the ground to passing electrical current.
Sensitive to geological variations, changes in groundwater saturation, and the
presence of contaminants. (Imaging by ERT – analogous to medical imaging)
Material
Resistivity (Ohm.m)
Clay
Low
Sand and gravel
Moderate
Concrete
High
Granite
Very high
• Why use ERT?
• Volumetric information
• Non-invasive
• Rapid
• Composition
• Moisture content
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Medical imaging
Geophysical
imaging
Field ERT – What does it look like ?
Resy Array: 64 electrodes x 0.5 m electrode spacing
BIONICS, Hexham
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Field ERT – What does it look like ?
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Solar array, 20W
PRIME Instrument:
Field installation
Antenna
Solar
regulator
GSM router
PRIME
Instrument
Sensor array
cables
Batteries
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PRIME - Hardware
PRIME Instrument:
Modular: 16 x 16 (256 electrodes)
HV Supply: 100V (200 V max)
Current: 0.1 - 100mA
Measurement channels: 7-off
Gain setting: 1, 10
SP Null: +/- 2.5 VDC
Measurement accuracy:
ADC +/-5V range: 38uV*
ADC +/- 10V range: 72uV*
Power: 12 VDC (10 W)
Setup & Control:
Command file & Scheduling via Ethernet
Access via Web Portal
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PRIME - Hardware
SDI Interface:
• SDI-12 is a multi-drop interface that can communicate with multiparameter sensors
• 3-Wire interface: Serial, +12V, GND
• Single SDI-Interface supports up to 36 variables
• Each SDI-Device has own identity (0-9)(a-z)
Decagon 5TE moisture sensor
• 3 Variables: Temp, Moisture, EC
Vaisala weather station
• Multiple Variables: Temp, Rainfall, Humidity
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Electrical Resistivity Tomography Imaging – How does it work?
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Electrical Resistivity Tomography Imaging – How does it work?
Data Collection
Data Collection
Resistivity
Instrument
Layer 1
Layer 2
Layer 3
X X X X X X X X X
X X X X X X X
X X X X X
Data Inversion
Computer
Elevation
(mAOD)
Sand and Gravel
Overlying Sandy Till
140
Electrical Model
135
Till
120
160
130
125
120
115
Bromsgrove Sandstone
110
105
100
53
Data Inversion
Electrical Image
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70
94
126 168 224
Resistivity (Wm)
300
400
80
40
Till
Estimated
Groundwater
Level
0
PRIME Platform: Remote Delivery of Condition Information
Software
Database Management
System &
Inversion Server
Data
Storage
Resistivity
images
Inversion
& web
delivery
Parameter
conversion
Time
Geoelectrical
Command Files
Data
& Schedule
Hardware
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Moisture content
images
Automatic
alarm
Early
warning
Time
Aged Embankment : Great Central Railway, East Leake
 GCR Extension: Northern Division - 1899
 Barnstone Cutting Fill Northwards
 End Tip: Westbury / Blue Anchor Mudstones
Nottingham
1 km
Loughborough
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(after Dow, 1962)
PRIME – Software (parameter translation)
t24 t25t26 t27
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t28
Soil moisture
relationships can be
used to translate
resistivity images into
moisture content
Cause / Effect:
% Change in
Gravimetric Moisture Content
Linking the surface to the subsurface
Space
Time
Predicted
positions
GPS measured
positions
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PRIME – Time –Lapse Volumetric Monitoring
Contaminant
transport
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PRIME – Ground Water Rebound
Resistivity monitoring results
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Automated image analysis
PRIME – Applications across the UK
1. Old Dalby Railway Cutting
(Network Rail)
2. Llangynidr Canal Embankment
(Canal & River Trust)
3. Newbury Road Cutting
(Southampton University)
4
1
2
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7
5
3
4. Aldbrough Coastal Landslide
5. Charlton Kings Landslide
6. Boxford Water Meadows (CEH)
7. Bristol Water Test Site
(Birmingham University)
6
Future Gazing: Non-Invasive Imaging for Asset Information Delivery
N
N
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N
East Leake Embankment – Stiffness Model ( MPa ): Aerial drape
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East Leake Embankment – Stiffness Model ( MPa ): Fade aerial drape
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East Leake Embankment – Stiffness Model ( MPa ): 3D voxelated stiffness > 80 MPa
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Time Lapse 3D Models: Real-time Asset Condition Indicators
Liquid limit
Plastic limit
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Delivery Platform: Rapid, Remote Control & Information Access
Control / Delivery:
Remotely:
On Time
IT Systems-Media
Telecom
Connection
Field
Installation
Embankments
Permanent or
Semi-Permanent
Asset Management
Renewable
Power
N
Remote
Monitored
Dynamically
Configurable
Cuttings
Web Servers
Database
Management
System
Dams
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Alerts: Messaging:
Threshold exceedance
PRIME
– Near Real-Time Geotechnical Images via Geophysical Proxy
Site Database
Resistivity
images
Inversion
& web
delivery
Moisture content
images
Parameter
conversion
Time
Automatic
alarm
Early
warning
Time
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Database management system: Multi-site management
Parameter translation
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Computer vision / pattern recognition
Early warning / alarm thresholds
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© NERC All rights reserved
Resistivity to moisture content & groundwater quality
Resistivity to ground motion
Resistivity to subsurface temperature
PRIME - Summary
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PRIME instrument has been developed – on budget and to
specification
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Modular, low power (10 W), low cost (~£7k)
Applicable to a wide range of monitoring applications
Multiple installation planned for 2015
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PRIME information delivery progressing well
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Future development
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© NERC All rights reserved
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Working with ITM Monitoring to interface with industry standards
Developing automated image analysis approaches with
Nottingham University
New grant applications to develop and demonstrate workflow
Development of high-power PRIME system (ESIOS?)