Journal of the Korea Institute of Building Construction (한국건축시공학회지)

The Korean Institute of Building Construction (한국건축시공학회)
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An Experimental Study on the Evaluation of EMP Shielding Performance of Concrete Applied with ATMSM Using Zn-Al Alloy Wire

Zn-Al 합금 선재를 이용한 금속용사 공법 적용 콘크리트의 전자파 차폐 성능 평가에 관한 실험적 연구

  • Received : 2019.02.19
  • Accepted : 2019.05.02
  • Published : 2019.06.20
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Abstract

EMP (Electromagnetic Pulse) usually means High Power Electromagnetic Wave (HPEM). In the case of the shielding plate against the EMP, there is a possibility of deterioration of the electromagnetic wave shielding performance due to the skill of the constructor, bad construction, deformation of the shielding plate at the connection portion (joint portion). The inefficient use of space due to the separation distance is also pointed out as a problem. Therefore, this study aims to derive the optimum electromagnetic shielding condition by applying ATMSM to concrete as a part of securing electromagnetic wave shielding performance with reflection loss against concrete wall. Experimental parameters included concrete wall thickness and application of Zn-Al ATMSM. For the concrete wall, the wall thickness was 100 to 300mm, which is generally applied, and experimental parameters were set for the application of Zn-Al metal spraying method to evaluate electromagnetic shielding performance. Experimental results showed that as the thickness increases, the electromagnetic shielding performance increases due to the increase of absorption loss. In addition, after the application of Zn-Al ATMSM, the average shielding performance increased by 56.68 dB on average, which is considered to be increased by the reflection loss of the ATMSM. In addition, it is considered that the shielding performance will be better than that when the conductive mixed material and the ATMSM are simultaneously applied.

EMP(Electromagnetic Pulse)는 통상적으로 고출력 전자기파 (High Power Electromagnetic: HPEM)를 의미한다. EMP를 차폐하기 위한 차폐 판의 경우, 현장 적용 시, 용접 및 볼트의 연결부(접합부)에서 시공자의 숙련도 및 불량시공, 차폐판의 변형 등으로 인한 전자파 차폐성능 저하의 가능성을 유발하고 있으며, 또한 벽체로부터 이격거리로 인한 비효율적인 공간 활용이 문제점으로 지적 되고 있다. 따라서, 본 연구는 콘크리트 벽체를 대상으로 반사손실에 대한 전자파 차폐성능을 확보하기 위한 일환으로서, 콘크리트에 금속용사 공법을 적용하여 최적의 전자파 차폐 조건을 도출하고자 한다. 실험변수로는 콘크리트 벽체 두께, Zn-Al 금속용사 적용 유무이다. 콘크리트 벽체의 경우, 일반적으로 적용되어지고 있는 벽체 두께인 100~300mm이며, 또한 전자파 차폐성능에 관한 Zn-Al 금속용사 공법의 실효성을 평가하기 위해 적용 유무로 구분하여 실험변수를 설정하였다. 실험 결과 두께가 증가할수록 흡수 손실의 증가로 인해 전자파 차폐성능이 증가하였다. 또한 Zn-Al 금속용사 적용 후 모든 시험체에서 평균 56.68 dB의 상당한 차폐성능 증가를 보였으며, 이는 금속용사 피막의 반사손실에 의하여 증가된 것으로 판단된다. 또한, 전도성 혼입재료와 금속 용사 피막을 동시에 적용할 경우 보다 우수한 차폐성능을 나타낼 것으로 판단된다.

Keywords

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Figure 1. Floor plan of a conventional EMP shielding facility[9]

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Figure 2. Mechanism of EMP shielding

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Figure 3. Specification of the name of specimens

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Figure. 4. Specimens of EMP shielding concrete

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Figure 5. Diagram of ATMSM[23]

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Figure 6. ATMSM procedure using Zn-Al wire

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Figure 7. Set up of experimental specimen

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Figure 8. Results of total specimens

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Figure 9. The increment of SE by ATMSM

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Figure 10. Shielding effectiveness of ATMSM specimens

Table 1. Experimental variables

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Table 2. Mix proportion of concrete

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Table 3. Physical properties of total specimens

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Table 4. Shielding effectiveness of non-ATMSM specimens

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Table 5. Shielding effectiveness of total specimens

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Table 6. The increment of SE by ATMSM

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References

  1. IEC 61000-2-9. Electromagnetic compatibility (EMC) - Part 2: Environment - Section 9: Description of HEMP environment - Radiated disturbance. International Electrotechnical Commission; 1996. 49 p.
  2. Kim HS. Truth of EMP threat and development plan. Defence Tech. 2013 Aug;414:98-103.
  3. Savage E, Gilbert J, Radasky W. The Early-Time (E1) High-Altitude Electromagnetic Pulse (HEMP) and Its Impact on the U.S. Power Grid. Goleta (CA): Metatech Corporation; 2010 Jan. 168 p. Report No.: Meta-R-320. Contract No.: 6400009137. Supported by Oak Ridge National Laboratory.
  4. Gurevich V. Protection of substation critical equipment against intentional electromagnetic threats. London: Wiley; 2017. 240 p. https://doi.org/10.1002/9781119271444
  5. Foster JS, Gjelde E, Graham WR, Hermann RJ, Kluepfel HM, Lawson RL, Soper GK, Wood LL, Woodard JB. Report of the commission to assess the threat to the United States from electromagnetic pulse (EMP) attack. Virginia: Electromagnetic Pulse(EMP) Commission; 2008. 208 p.
  6. MIL-STD-188-125-1. High-altitude electromagnetic pulse (HEMP) protection for ground-based C41 facilities performing critical, time-urgent missions - part 1 fixed facilities. Department of Defense Interface Standard; 2005. 106 p.
  7. IEEE-299. IEEE Standard Method for Measuring the Effectiveness of Electromagnetic Shielding Enclosures. IEEE Standards Association; 2006. 50 p. https://doi.org/10.1109/ieeestd.2007.323387
  8. Kim YS, Choi IK, Kim SS. Analysis of electromagnetic wave shielding effectiveness from electrical conductivity of metalized conductive sheets. Korean Journal of Materials Research. 1999 Aug;9(9):913-8.
  9. Lee HS, Choe HB, Baek IY, Singh JK, Ismail MA. Study on the shielding effectiveness of an arc thermal metal spraying method against an electromagnetic pulse. Materials. 2017 Oct;10(10):1-14. https://doi.org/10.3390/ma10101155
  10. Nam IW, Kim HK, Lee HK. Influence of silica fume additions on electromagnetic interference shielding effectiveness of multi-walled carbon nanotube/cement composites. Construction and Building Materials. 2012 May;30:480-7. https://doi.org/10.1016/j.conbuildmat.2011.11.025
  11. Kim HK, Nam IW, Lee HK. Enhanced effect of carbon nanotube on mechanical and electrical properties of cement composites by incorporation of silica fume. Composite Structures. 2014 Jan;107:60-9. https://doi.org/10.1016/j.compstruct.2013.07.042
  12. Khushnood RA, Ahmad S, Savi P, Tulliani JM, Giorcelli M, Ferro GA. Improvement in electromagnetic interference shielding effectiveness of cement composites using carbonawceous nano/micro inerts. Construction and Building Materials. 2015 Jun;85:208-16. https://doi.org/10.1016/j.conbuildmat.2015.03.069
  13. Cao J, Chung DDL. Colloidal graphite as an admixture in cement and as a coating on cement for electromagnetic interference shielding. Cement and Concrete Research. 2003 Nov;33(11): 1737-40. https://doi.org/10.1016/s0008-8846(03)00152-2
  14. Wu J, Chung DDL. Improving colloidal graphite for electromagnetic interference shielding using 0.1 lm diameter carbon filaments. Carbon. 2003 Jan;41(6):1313-15. https://doi.org/10.1016/s0008-6223(03)00033-2
  15. Chung DDL. Exfoliation of graphite. Journal of Materials Science. 1987 Dec;22(12):4190-8. https://doi.org/10.1007/bf01132008
  16. Chung DDL. Review graphite. Journal of Materials Science. 2002 Apr;37(8):1475-89. https://doi.org/10.1023/a:1014915307738
  17. Luo X, Chung DDL. Electromagnetic interference shielding reaching 130 dB using flexible graphite. Carbon. 1996 Jan;.34 (10):1293-4. https://doi.org/10.1016/0008-6223(96)82798-9
  18. Kim YJ, Yeman DM, Kim BJ, Yi CK. Effect of fiber geometry on the electromagnetic shielding performance of mortar. Computers and Concrete. 2016 Feb;17(2):281-94. https://doi.org/10.12989/cac.2016.17.2.281
  19. Wen S, Chung DDL. Electromagnetic interference shielding reaching 70 dB in steel fiber cement. Cement and Concrete Research. 2004 Feb;34(2):329-32. https://doi.org/10.1016/j.cemconres.2003.08.014
  20. KS F 2405. Standard test method for compressive strength of concrete. Seoul(Korea). Korea Standard; 2017. 12 p.
  21. KS L 5201. Portland cement. Seoul(Korea). Korea Standard; 2016. 16 p.
  22. KS F 2403. Standard test method for making and curing concrete specimens. Seoul(Korea). Korea Standard; 2014. 14 p.
  23. Lee HS, Park JH, Singh JK, Ismail MA. Protection of reinforced concrete structures of waste water treatment reservoirs with stainless steel coating using arc thermal spraying technique in acidified water. Materials. 2016 Apr;9(9):1-20. https://doi.org/10.3390/ma9090753
  24. ASTM D 4935. Standard test method for measuring the electromagnetic shielding effectiveness of planar materials. PA: American Society of Testing Materials; 2010. 11 p. https://doi.org/10.1520/d4935-10
  25. Chung YC, Kang TW, Chung NS. Electromagnetic shielding effectiveness of the composite materials in the far field region. Electromagnetic Wave Technology. 1994 Mar;5(1):31-9.