A Prescription for Healthier, Longer-Lived Levees and Dams
Researchers at Rensselaer Polytechnic
Institute have secured a $7 million NIST TIP grant to
develop a comprehensive system for monitoring and
assessing the condition of aging levees and dams. The new
system, which uses satellite-based radar, small ground
sensors, and GPS to collect continuous, real-time data,
could help to significantly reduce the risk of
catastrophic levee failures.
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Researchers launch $7 million project to develop new
system for assessing the condition of flood-control
infrastructure
Researchers at Rensselaer Polytechnic Institute are leading
a $7 million project to develop a new comprehensive system for
monitoring and assessing the condition of aging levees and
dams.
The four-year project, which includes $3.5 million in funding
from a U.S. National Institute of Standards and Technology
(NIST) Technology Innovation Program grant, aims to create an
integrated suite of technologies and methods for ensuring the
reliability and safety of flood-control infrastructure.
Rensselaer will partner with Geocomp Corp. on this new
framework, which incorporates satellite-based radar with GPS
and locally installed sensors. Such a system could help to
significantly reduce the risk of catastrophic events akin to
the 2005 New Orleans levee failure during Hurricane
Katrina.
“The unique ability of Rensselaer faculty to bring together
a large-scale, integrated approach to address the problem of
catastrophic flood control will help bring safety and security
to millions of people in the future,” said Rensselaer Provost
Robert Palazzo.
“The challenges of monitoring and assessing large
infrastructure systems in varying stages of deterioration are
among the most pressing we face as a nation,” said David
Rosowsky, dean of engineering at Rensselaer.
“Currently, most infrastructure assessments are based on
infrequent visual inspections of the surface condition of
levees and dams, which in reality reveal very little about the
internal condition and performance of these structures. It’s
like a medical doctor conducting an annual checkup based solely
on the external appearance of a patient,” said
Mourad Zeghal, associate professor in the Department of
Civil and Environmental Engineering at Rensselaer, who is
leading the project.
“Our project sets out to develop a new, more effective means
to continuously monitor and analyze, in real time, the internal
and external health of levees and dams. The proposed framework
is cost-effective, robust, minimally invasive, and should boost
the safety and reliability of our national flood-control
infrastructure,” he said.
The project’s capstone experiment includes participating in
a $5 million test by the U.S. Army Corps of Engineers that
involves intentionally breaching, or loading until failure, a
full-scale
levee.
Co-investigators on the project are Tarek
Abdoun, the Iovino ’73 Career Development Professor in
Civil Engineering at Rensselaer and acting head of the
Department of Civil and Environmental Engineering, and Birsen Yazici,
associate professor in the Department of Electrical, Computer,
and Systems Engineering at Rensselaer. Abdoun led Rensselaer’s
physical modeling research team that clarified
the failure mechanisms of some of the New Orleans levees
during Hurricane Katrina, providing critical feedback to the
corresponding numerical analyses. Yazici is leading an $800,000
U.S. Air Force research
project to create a new laboratory for developing and
testing next-generation radar systems.
Among the long-term monitoring techniques proposed for the
levee assessment framework is InSAR, or satellite-based
interferometric synthetic aperture radar measurements. InSAR
will capture and analyze high-resolution satellite images of
levees and dams, and measure how far these structures have
shifted or sunk due to environmental changes such as rain,
floods, tremors, or even aging. InSAR measurements are accurate
down to the millimeter scale.
The proposed framework also calls for sensor arrays to be
installed into the ground beneath and around levees and dams.
These SAPP (shape-acceleration-pore pressure) arrays are
inexpensive and will help to accurately measure soil
deformation, vibration, and pore pressure at critical points of
a flood-control system. To bridge the gap between InSAR
satellite data and below-ground SAPP measurements, the
researchers will augment the framework with a network of
high-resolution GPS sensors to track the physical movement of
structures.
Data collected from the three systems will be integrated
into an automated “smart network” that provides, for the first
time, a long-term continuous assessment of the health of levee
systems from both underground and aerial perspectives, Zeghal
said. In case of a levee failure, data collected by the
proposed automated monitoring system will be used to organize a
quick emergency response to repair levees and minimize the
extent of flooding.
Collected data will also be paired with computational
simulation techniques to build accurate, predictive models of
how different levees should react to different environmental
conditions. Such models will be invaluable for developing plans
to mitigate levee damage and respond to disasters, Zeghal said.
The new framework will also provide quantitative assessments
that will better allow federal and local governments to
prioritize where infrastructure repairs are most needed.
“The combination of modeling and measurements will provide
significantly more accurate information about the health state
of levees than measurements alone,” Abdoun said. “The
successful development and implementation of this framework
will have high reward, enabling better management of more
reliable flood-control infrastructure.”
“Once complete, this technology could easily be adapted and
applied to similar systems for monitoring the health of
highways, roads, and coastal infrastructures,” Yazici said.
“This framework may also be used to assist in assessing
geohazards such as landslides and sinkholes.”
For additional information on levee and earthquake research
conducted at Rensselaer, visit: http://nees.rpi.edu. For more
information on Rensselaer’s contributions to national efforts
in responding to Hurricane Katrina, visit:
http://www.eng.rpi.edu/magazine/img/sp06/pdf/Sp06_SoeNews_Katrina-1.pdf.
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Published
December 17,
2009 |
Contact: Michael Mullaney
Phone: (518) 276-6161
E-mail: mullam@rpi.edu |
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