NS710: Feasibility of InSAR for Continuous Monitoring of Ground Deformation and Performance Tracking of Geotechnical Assets
Problem
In Minnesota, ground movements (e.g., landslides, land subsidence, etc.) have led to significant damage and disruption to the state’s highway network. These geohazards can lead to lane closures, traffic delays, and emergency repairs. While predicting these types of events beforehand is difficult, continuous, and accurate monitoring of ground deformation along roads is crucial to identify higher risk areas before they develop into major failures. Ground deformation is commonly first reported by passing motorists or maintenance personnel. After receiving these reports, investigations are completed involving geotechnical and/or geophysical surveys, and instrumentation, such as inclinometers or survey monuments may be installed to monitor movements. These reactive approaches to monitoring can be effective at smaller sites with a history of movement, but they cannot be used to get continuous measurements of deformation over an area and can only be applied to sites that have already moved enough to lead to signs of distress. Additionally, they can provide measurements with limited spatial coverage and require considerable resources and effort to install.
Objective
The main objective of this research is to develop an automated warning system that can alert MnDOT staff of areas where abnormal ground deformation (e.g., landslides, subsidence, and sinkholes) is occurring along Minnesota interstate highways, allowing them to proactively intervene. This warning system will combine data from high spatial resolution InSAR measurements, optical remote sensing data, and deep learning algorithms to automatically detect and continuously monitor deformations across large spatial regions. Implementation of this proactive monitoring approach is expected to increase the safety and reliability of Minnesota’s transportation system. This study will also help MnDOT continue building its Geotechnical Asset Management (GAM) program by assessing the feasibility of InSAR for tracking performance of geotechnical assets (e.g., retaining walls, slopes, pavement foundations, etc.).
Previous research
Slope vulnerabilities studies previously completed at MnDOT will be used to inform site selection for validation of InSAR framework.
- MnDOT Slope Vulnerability Assessments - Phase 1 (completed)
- MnDOT Slope Vulnerability Assessments - Phase 2 (completed)
- Phase 3 MnDOT Slope Vulnerability Assessments (completed)
- Phase 4 MnDOT Slope Vulnerability Assessments (completed)
- Vulnerability Assessments of Critical Slope Areas Using Advanced Monitoring Techniques (active)
Strategic priorities
- Advancing Equity: This work aims to identify areas which are at higher risk for deformation or failure and resulting consequences. The technology can also support a larger geographical area than previous methods.
- Asset Management: This work could potentially improve statewide monitoring and warning of ground movement through continuous monitoring over larger areas even before visible distress occurs. Furthermore, it can help in the development of a tool for continuous tracking of performance of geotechnical assets.
- Safety: Implementation of this proactive monitoring approach is expected to increase the safety and reliability of Minnesota’s transportation system.
- Climate Change & Environment: Expected increase in storm events and flooding necessitates a system to monitor ground movements near infrastructure.
Expected outcomes
- New or improved business practices, procedure, or process
- New or improved tool or equipment
- New or improved decision support tool, simulation, or model/algorithm (software)
Expected benefits
The numbers 1 and 2 indicate whether the source of the benefit measurement is from:
- A specific research task in your project that supports measuring this particular benefit, or
- Implementation of the research findings (anticipating positive results)
- Construction Savings (2)
- Cost savings from proactively assessing and stabilizing problematic locations highly susceptible to geohazards along interstate highway
- Decreased Engineering/Administrative Cost (1)
- Demonstrate savings from point monitoring of geotechnical assets (e.g., using inclinometers) to a spatiotemporal approach with satellite. Cost of installation, maintenance and analysis of point monitoring will be compared with the cost of analyzing InSAR data. Also, if necessary or needed cost of high-resolution satellite will be included in assessment of benefit (instead of low resolution free images).
- Safety (2)
- Implementation of this proactive spatiotemporal monitoring approach is expected to increase the safety and reliability of Minnesota’s transportation system. By selecting a historical problematic site along interstate, a comparison can be made between what was done to mitigate/fix failure/issue using current monitoring tools with this proposed spatiotemporal InSAR monitoring approach.
- Also, using remote sensing technologies to minimize inspector time in the field.
- Risk Management (2)
- New tools and systems may help inform road crews and engineers of ground deformation near highways and help with development of a formal risk assessment framework for geotechnical assets.
- Asset Management (2)
- This work could potentially improve statewide monitoring and warning of ground movement through continuous monitoring over larger areas even before visible distress occurs. Furthermore, it can help in the development of a tool for continuous tracking of performance of geotechnical assets.
Technical advisory panel
- Michael Cremin, AMPO
- Joseph Podolsky, OMRR – Research Section
- Jason Hedeen, OMRR – Geotechnical Section
- Micah Holzbauer, OMRR – Geotechnical Section