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Correlation Analysis between Strength and Defect of Nano-Cementitious Composites using Ultrasonic Pulse Velocity.
Yangsub Shin1, Sanghyeon Cho1, Hyojeong Yun1
1Department of Civil Engineering, Kyung Hee Univeristy, 1732 Deokyoung-Daero, Giheung-gu, Yongin-si 17104, Republic of Korea.
Nanomaterials (Basel, Switzerland)
|April 13, 2023
Summary
Researchers studied defects in nano-cementitious composites using ultrasonic and compressive tests. Larger defects significantly reduced ultrasonic pulse velocity and compressive strength, revealing a key correlation for material quality assessment.
Area of Science:
- Materials Science
- Civil Engineering
- Nanotechnology
Background:
- Nanomaterials enhance cementitious composites but can cause defects like agglomeration.
- Internal defects negatively impact the mechanical properties of nano-cementitious composites.
Purpose of the Study:
- To investigate the effect of internal defect size on nano-cementitious composites.
- To correlate ultrasonic non-destructive testing with compressive strength in defective composites.
Main Methods:
- Specimens of nano-cementitious composites with controlled internal defects were prepared using multi-walled carbon nanotubes (MWCNTs).
- Ultrasonic pulse velocity was measured up to 30 curing days.
- Compressive strength tests were conducted after ultrasonic measurements.
Main Results:
- Ultrasonic pulse velocity decreased by up to 9.6% with increasing defect size.
- Compressive strength decreased by up to 35.7% with increasing defect size.
- A strong correlation was found between ultrasonic pulse velocity and compressive strength relative to defect size.
Conclusions:
- Ultrasonic non-destructive testing can effectively detect internal defects in nano-cementitious composites.
- Ultrasonic pulse velocity serves as a reliable indicator for predicting the mechanical performance of these materials.
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