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Electromagnetic Wave Shielding Properties of Amorphous Metallic Fiber-Reinforced High-Strength Concrete Using
Sangkyu Lee1, Gyuyong Kim1, Hongseop Kim2
1Department of Architectural Engineering, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, Korea.
Materials (Basel, Switzerland)
|November 27, 2021
Summary
Amorphous metallic fibers enhance concrete
Area of Science:
- Materials Science
- Civil Engineering
- Electrical Engineering
Background:
- High-strength concrete requires advanced materials for enhanced properties.
- Electrical conductivity and electromagnetic shielding are critical for advanced concrete applications.
- Fiber reinforcement significantly influences concrete's physical and electrical characteristics.
Purpose of the Study:
- To evaluate the electrical conductivity and electromagnetic shielding effectiveness of high-strength concrete incorporating amorphous metallic fibers (AMFs) and hooked-end steel fibers (HSFs).
- To investigate the impact of moisture content and aging on these properties.
- To compare the performance of AMFs and HSFs in concrete composites.
Main Methods:
- Fabrication of high-strength concrete specimens with varying fiber types (AMFs, HSFs) and volume fractions.
- Measurement of electrical conductivity and electromagnetic shielding effectiveness at 28 and 208 days.
- Controlled assessment of moisture content's influence on the evaluated properties.
Main Results:
- AMFs facilitate superior conductive network formation due to lower density and higher dispersibility compared to HSFs.
- Electromagnetic shielding effectiveness (SE) directly correlates with increased electrical conductivity.
- SE approaches saturation with AMF volume fractions exceeding 0.5 vol.%, achieving >80 dB at 0.5 vol.% AMF with low moisture after 208 days.
- Reduced moisture content is crucial for conservative SE evaluation.
- AMFs offer excellent SE at lower contents than HSFs.
Conclusions:
- Amorphous metallic fibers are highly effective in enhancing both electrical conductivity and electromagnetic shielding performance of high-strength concrete.
- The study highlights the potential of AMFs as a superior alternative to steel fibers for electromagnetic shielding applications in concrete.
- Optimizing fiber content and managing moisture are key for maximizing the shielding capabilities of fiber-reinforced concrete.
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