Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
PRIME: Proactive Infrastructure Monitoring and Evaluation PRIME MOVERS: Jon Chambers / Philip Meldrum / Paul Wilkinson Geophysical Tomography Team © NERC All rights reserved PRIME – • • 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 © NERC All rights reserved 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 © NERC All rights reserved Medical imaging Geophysical imaging Field ERT – What does it look like ? Resy Array: 64 electrodes x 0.5 m electrode spacing BIONICS, Hexham © NERC All rights reserved Field ERT – What does it look like ? © NERC All rights reserved Solar array, 20W PRIME Instrument: Field installation Antenna Solar regulator GSM router PRIME Instrument Sensor array cables Batteries © NERC All rights reserved 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 © NERC All rights reserved 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 © NERC All rights reserved Electrical Resistivity Tomography Imaging – How does it work? © NERC All rights reserved 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 © NERC All rights reserved 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 © NERC All rights reserved 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 © NERC All rights reserved (after Dow, 1962) PRIME – Software (parameter translation) t24 t25t26 t27 • © NERC All rights reserved 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 © NERC All rights reserved PRIME – Time –Lapse Volumetric Monitoring Contaminant transport © NERC All rights reserved PRIME – Ground Water Rebound Resistivity monitoring results © NERC All rights reserved 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 © NERC All rights reserved 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 © NERC All rights reserved N East Leake Embankment – Stiffness Model ( MPa ): Aerial drape © NERC All rights reserved East Leake Embankment – Stiffness Model ( MPa ): Fade aerial drape © NERC All rights reserved East Leake Embankment – Stiffness Model ( MPa ): 3D voxelated stiffness > 80 MPa © NERC All rights reserved Time Lapse 3D Models: Real-time Asset Condition Indicators Liquid limit Plastic limit © NERC All rights reserved 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 © NERC All rights reserved 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 • • Database management system: Multi-site management Parameter translation • • Computer vision / pattern recognition Early warning / alarm thresholds • • • © NERC All rights reserved Resistivity to moisture content & groundwater quality Resistivity to ground motion Resistivity to subsurface temperature PRIME - Summary • PRIME instrument has been developed – on budget and to specification • • • Modular, low power (10 W), low cost (~£7k) Applicable to a wide range of monitoring applications Multiple installation planned for 2015 • PRIME information delivery progressing well • Future development • • © NERC All rights reserved • • 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?)