1. Purpose of This Research
Simulating an Earth Quake
Damaging Cement Samples
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Above, a sample of cement with built in probes and a 1/4 Inch damage
 Sawing into samples imitate cracks formed due to Earthquakes or
movement.
 (Below) Data shows the change in resistance after induced damage.
 Resistance increases by approximately a thousand Ohms.
• Using Fourier analysis, the change in resistance is tracked and shows at what frequency the
sample reacts to. This can be used to indicate what causes the vibration, man or nature.
Above are samples of cement and CNT epoxy board samples
Cement samples are sawn into at 1/8th of an inch increments
CNT epoxy are drilled into at 1/8th of and inch diameter increments.
Using a four probe Agilent Ohm meter, the electrical resistance and its
change after damage are recorded
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Hypothesis
 Cement samples are shaken at up to 7g forces in
order to simulate the stress of an earthquake.
 Electrical resistance sees a spike when vibrated.
 Violent vibrations correlate to greater resistance
changes.
 Damaged and undamaged samples show nearly
equal amounts of resistance change.
 Carbon Nanotube Epoxy Resin is regarded as the future of engineering.
 It is the go-to material for light weight durability.
 CNT Epoxy is rested for its resistance change due to damage. To
simulate impacts to vehicles that use this materials.
 Samples are drilled at 1/8th of an inch increments in diameter
 After physical testing, this model is simulated using COMSOL
Multiphysics, and damages with different shapes and orientations.
Using electricity to measure damage in materials, this
research aims to use an alternate method of locating and indicating
the magnitude of damage in what are called, piezo-resistive
materials. This method of detecting damage uses a time saving and
cost effective approach as opposed to traditional methods.
Methodology
Damaging piezo-resistive material will increase its electrical
resistance. Using several probes, damage can be located and
magnitude can be predicted without being seen.
 Probes are placed on cement and Carbon Nanotube (CNT) epoxy
resin samples.
 Using an Agilent four-wire Ohm meter, resistance is recorded.
 The materials are damaged and the change in resistance are
recorded on several probes.
 Using the changes in resistance recorded by the probes,
location can be determined.
• Hoan bridge collapse, Dec. 2000. One of many failed/failing structures in America
where collapse could have been preventable if properly monitored.
Carbon Nanotube Epoxy
The following potion of this research was to learn
if there was correlation between the shape of the
damage and its change to the board’s resistance. The
change in resistance is greatly influenced by its shape
and orientation and it soon became apparent that a
cylindrical hole was the most effective method of
increasing the resistance.
Cone damages were simulated and compared to
cylindrical holes of equal volume.
• The dimension of this truncated
cone are 0.25”-0.75”-
0.03”(Middle and Right).
Regardless of the orientation of
this cone a cylinder of equal
volume (Left) has greater
resistance change.
• When shaped like
a normal cone,
with dimensions
0.81”-0.015”.
The damage
shows less
resistance change
than that of a
cylinder.
• These two board models show how percent difference between probes change when
a damage between them are placed at different locations.
Acknowledgments
To conclude, the piezo-resistive materials, CNT epoxy resin
and cement show clear signs of resistance change when damaged
or vibrated. The equipped probes measure resistance before and
after and can be used as an alert to signify a change in the
materials’ shape or whether the structure is being compromised.
The cement samples show clear signs of resistance change
when vibrated and also when cracked. Probes attached to buildings
can be used as useful indicators ‘see’ within the structure and
determine what may be in need for repairs.
Carbon Nanotube epoxy resin, used in modern vehicles and
many lightweight applications are strong but brittle and like cement,
show a clear change in resistance when damaged. The damage
can be picked up by probes on the board’s surface and are used to
locate magnitude of damage and location.
The use of resistance to measure damage has the potential
to be a remarkably useful tool in assessment of buildings and
vehicles. This method can be the next step to revolutionizing repair
and safety inspections.
Conclusion
 Future research will focus on
placing probes on buildings and
vehicles.
 Analyzing the change in
electrical resistance on building
pillars and frames.
 Analyzing electrical resistance
change as vehicles using CNT
parts are damaged.
 Studying projectile damage and
how it affects resistance.
Special Thanks to:
CUNY Research Scholars Program
Director of Research Dr. Alona Bach
Mentor: Dr. Mahmoud Ardebili
Analysis of Piezo Resistive Materials
By:Shivron Sugrim, Mentor: Doctor Mahmoud Ardebili
Borough of Manhattan Community College 199 Chambers st New York, NY, 10007
CUNY
Research
Scholars
Program