Smart concrete: Concrete that can sense stresses

1. Company
LOGO
Smart Concrete
KIRTAN ADHIKARI EDC 2010050
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2. CONTENT
1. INTRODUCTION
2. INVENTOR AND INVENTION
3. SELF SENSING CONCRETE
4. LABORATORY EXPERIMENT
5. RESULT AND DISCUSSION
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3. INTRODUCTION
Concrete that is itself a sensor of strain or stress.
The sensing ability is not due to the embedment or attachment of sensors.
 The concrete has been modified through the use of admixtures so that it becomes a sensor
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4. INTRODUCTION
The sensing ability of smart concrete are based on the change of electrical resistance.
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5. INVENTOR AND INVENTION
Invented by Professor Deborah Chung in University at Buffalo, State University of New York. (1993)
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6. Self Sensing Concrete
1.Smart Concrete Produced From Short Carbon Fibres
2.Smart Concrete Produced from CNTs
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7. Self Sensing Concrete
1.Smart Concrete Produced From Short Carbon Fibres
 Contain short carbon fibres, typically 5 mm in length
Fibre content is 0.2 vol. % of cement
Silica fume content is 15% by weight of cement
Methylcellulose content is 0.4% by weight of cement
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8. Self sensing concrete
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9. Self sensing concrete
2. Smart Concrete Produced from CNTs
Carbon nanotubes (CNTs) are seamless tubular structures.
The diameters of CNTs are in the range of 1~20 nm
 The lengths are in the range of 0.2~5 μm.
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10. Self sensing concrete
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11.  The mix was prepared with:
 Fibre content is 0.2 vol. % of cement
 Silica fume content is 15% by weight
of cement
 Methylcellulose content is 0.4% by
weight of cement
1. The mix was molded into square
shape with 2 embedded electrode, 1
cm apart.
2. The specimen were cured at standard
temperature of 20 degrees centigrade
and 100 % humidity.
3. Specimens were dried at temperature
of 50 degrees centigrade for 5 days.
EXPERIMENT
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12. EXPERIMENT
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13. EXPERIMENT
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14. RESULT AND DISCUSSION
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15. CONCLUSION
•The piezoresitive property of carbon nanotubes/CFs enables the composite to detect the stress/stain inside the pavement.
•Experimental results demonstrated that the CNT/cement composite function as excellent stress/strain sensors
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16. RFERENCES
REFERENCES
[1] B. Demirel, S. Yaziciog˘lu and N. Orhan. (December 2006). Electrical behaviour of carbon fibre-reinforced. Magazine of
Concrete Research, 7.
[2] Chung, D. D. (2006). The Road to Scientific Success. Singapore: World Scientific Pubilishing Co.Pte.Ltd.
[3] Chung, D. D. (1994). Carbon Fiber Composite. Washington: Butterworth-Heinemann.
[4] Chung, D. D. (13 October 1994). Strain sensor based on resistance change accompanying the reversible pull-out of
conducting short fibers in a less conducting matrix. Smart Mater. Strum.
[5] Dr. Xun Yu, Dr. Eil Kwon. (April 2012). Carbon Nanotube Based Self-sensing Concrete for Pavement. Washington:
University of Minnesota Duluth.
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