Journal of the Korea Concrete Institute (콘크리트학회논문집)

Korea Concrete Institute (한국콘크리트학회)
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Neutron Shielding Performance of Mortar Containing Synthetic High Polymers and Boron Carbide

합성 고분자 화합물 및 탄화붕소 혼입에 따른 모르타르의 중성자 차폐성능 분석

  • Min, Ji-Young (Structural Engineering Research Institute, Korea Institute of Civil Engineering and Building Technology) ;
  • Lee, Bin-Na (Structural Engineering Research Institute, Korea Institute of Civil Engineering and Building Technology) ;
  • Lee, Jong-Suk (Structural Engineering Research Institute, Korea Institute of Civil Engineering and Building Technology) ;
  • Lee, Jang-Hwa (Structural Engineering Research Institute, Korea Institute of Civil Engineering and Building Technology)
  • 민지영 (한국건설기술연구원 구조융합연구소) ;
  • 이빛나 (한국건설기술연구원 구조융합연구소) ;
  • 이종석 (한국건설기술연구원 구조융합연구소) ;
  • 이장화 (한국건설기술연구원 구조융합연구소)
  • Received : 2015.09.14
  • Accepted : 2015.12.30
  • Published : 2016.04.30
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Abstract

Concrete walls of neutron generating facilities such as fusion reactors and fission reactors become radioactive by neutron irradiation. Both low-activation and neutron shielding are a critical concern at the dismantling stage after the shutdown of facilities with a requirement of radioactive waste management. To tackle this, two types of additives were investigated in fabricating mortar specimens: synthetic high polymers and boron carbide. It is well known that a hydrogen atom is effective in neutron shielding by an elastic scattering because its mass is almost the same as that of the neutron. And boron is an effective neutron absorber with a big neutron absorption cross section. In this study, the effect of the type, shape, and size of polymers were investigated as well as that of boron carbide. Total 16 mix designs were prepared to reveal the effect of polymers on mechanical properties and neutron shielding performance. The neutron does equivalent of polymers-based mortar for fast neutrons decreased by 36 %, and the count rate of boron carbide-based mortar with regard to thermal neutrons decreased by 90 % compared to conventional mortar. These results showed that a combination of polymers and boron carbide compounds has potential to reduce the thickness of neutron shields as well as radioactive waste from reactors.

본 논문에서는 타 재료에 비해 수소 원소 함유량이 높아 고속 중성자 차폐에 유리한 합성 고분자 화합물과 중성자 포획단면적이 큰 붕소화합물을 각각 혼입한 모르타르를 대상으로 중성자 차폐성능을 분석하였다. 합성 고분자 화합물의 종류, 형상, 크기, 함량 및 붕소화합물의 함량에 따라 총 16개 모르타르 배합을 설계하였으며, 각 배합의 슬럼프 플로우, 28일 압축 및 인장강도를 측정하고, 고속 중성자 및 열중성자에 대한 차폐실험을 수행하였다. 합성 고분자 화합물의 선량 투과율은 모르타르 대비 최대 38.5%까지 감소하였으며, 공기 중 선량의 26.3%까지 차폐하였다. 붕소화합물을 혼입한 모르타르의 열중성자 차폐율은 최대 90.3%로 대부분의 열중성자를 차폐하였다. 비록 화합물 혼입에 의해 모르타르의 기본 특성은 저하되었으나, 표면 개질, 특수 혼화제 첨가 등 지속적인 연구를 통하여 성능 저하를 최소화할 수 있을 것으로 판단되며, 중성자 투과성능 역시 다양한 타입의 시험체 조합을 통한 레이어 시스템 도입 등으로 다양한 투과성능에 따른 맞춤형 설계를 제공할 수 있을 것이다.

Keywords

References

  1. Akkurt, I., Basyigit, C., Kilincarslan, S., Mavi, B., and Akkurt, A., "Radiation Shielding of Concretes Containing Different Aggregates", Cement and Concrete Composites, Vol.28, Issue 2, 2006, pp.153-157. https://doi.org/10.1016/j.cemconcomp.2005.09.006
  2. Basyigit, C., Uysal, V., Kilincarslan, S., Mavi, B., Gunoglu, K., Akkurt, I., and Akkas, A., "Investigating Radiation Shielding Properties of Different Mineral Origin Heavyweight Concretes", AIP conference proceedings, Vol.1400, 2011, pp.232-235.
  3. Lee, J. Y., "Development and Application of Low-Activation Cement", Cement, Vol.188, 2010, pp.27-37.
  4. Halverson, D. C., Pysik, A. J., Aksay, I. A., and Snowden, W. E., "Processing of boron carbide-aluminum composites", Journal of the American Ceramic Society, Vol.72, 1989, pp.775-780. https://doi.org/10.1111/j.1151-2916.1989.tb06216.x
  5. Sandia Laboratories Transportation Technology Center, "Development of Boron Carbide-Copper Cermets: Status Report", Department of Energy, Report SAND-78-2317, 1979, p.58.
  6. Sato., S., Maegawa, T., Yoshimatsu, K., Sato, K., Nonaka, A., Takakura, K., Ochiai, K., and Konno, C., "Development of a low activation concrete shielding wall by multi-layered structure for a fusion reactor", Journal of Nuclear Materials, Vol.417, No.1-3, 2011, pp.1131-1134. https://doi.org/10.1016/j.jnucmat.2010.12.302
  7. Cho, S. H., Do, J. B., Ro, S. G., and Do, C. H., "Fabrication and Characteristics of Resin - Type Neutron Shielding Materials for Spent Fuel Shipping Cask", Journal of Industrial and Engineering Chemistry, Vol.7, No.3, 1996, pp.597-604.
  8. Jun, J., Kim, J., Bae, Y., and Seo, Y. S., "Enhancement of dispersion and adhesion of B4C particles in epoxy resin using direct ultrasonic excitation", Journal of Nuclear Materials, Vol.416, 2011, pp.293-297. https://doi.org/10.1016/j.jnucmat.2011.06.014
  9. KS A ISO 14152, "Neutron radiation protection shielding-Design principles and considerations for the choice of appropriate materials", Korean Standards Association, 2012, p.77.
  10. http://mdportal.kaeri.re.kr/
  11. Morioka, A., Sakurai, S., Okuno, K., Sato, S., Verzirov, Y., Kaminaga, A., Nishitani, T., Tamai, H., Kudo, Y., Yoshida, S., and Matsukawa, M., "Development of 300C heat resistant boron-loaded resin for neutron shielding", Journal of Nuclear Materials, Vol.367-370, 2007, pp.1085-1089. https://doi.org/10.1016/j.jnucmat.2007.03.198
  12. KS L 5105, "Testing method for compressive strength of hydraulic cement mortar", Korean Standards Association, 2012, p.5.
  13. KS L 5104, "Testing method for tensile strength of hydraulic cement mortars", Korean Standards Association, 2012, p.8.
  14. ASTM C143, "Standard Test Method for Slump of Hydraulic- Cement Concrete", ASTM International, 2015, p.4.
  15. Park, H., Kim, J., and Choi, K.-I., "Neutron Spectrum Measurement at the Workplace of Nuclear Power Plant with Bonner Sphere Spectrometer", Journal of Nuclear Science and Technology, Supplement 5, 2008, pp.298-301.

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