Tunnel and Underground Space (터널과지하공간)

Korean Society for Rock Mechanics and Rock Engineering (한국암반공학회)
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Current Status of Demonstration Test to Investigate Erosion and Piping Phenomena of Buffer Material around Near Field Rock Mass and Introduction of BEPT

근계영역에서 완충재 침식, 파이핑 현상 규명을 위한 실증실험 현황 및 BEPT 실험 소개

  • Seungbeom Choi (Korea Atomic Energy Research Institute (KAERI)) ;
  • Chang-Ho Hong (Korea Atomic Energy Research Institute (KAERI)) ;
  • Ji-Won Kim (Korea Atomic Energy Research Institute (KAERI)) ;
  • Minhyeong Lee (Korea Atomic Energy Research Institute (KAERI)) ;
  • Eun-Soo Hong (HBC Inc.) ;
  • Jin-Seop Kim (Korea Atomic Energy Research Institute (KAERI))
  • 최승범 (한국원자력연구원) ;
  • 홍창호 (한국원자력연구원) ;
  • 김지원 (한국원자력연구원) ;
  • 이민형 (한국원자력연구원) ;
  • 홍은수 ((주)HBC) ;
  • 김진섭 (한국원자력연구원)
  • Received : 2024.08.06
  • Accepted : 2024.08.16
  • Published : 2024.08.31
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Abstract

Bentonite buffer material is an important component of engineered barrier designed for the safe disposal of high-level radioactive waste. Under certain groundwater conditions, erosion or piping phenomena of the material can happen, which may compromise the overall safety of the whole engineered barrier system. Previous domestic researches related to it have been conducted at a laboratory scale so that those are subject to some limitations, despite their valuable results. Therefore, KAERI (Korea Atomic Energy Research Institute) has planned the BEPT (Bentonite Erosion and Piping Test) to extend and validate the previous works at a field conditions. Prior to detailed experimental design, case studies that had been conducted by leading countries in disposal research were collected and analyzed. The analyses included suitable site conditions and system design, which were incorporated into the detailed design of BEPT. This technical report aims to introduce the previous researches and the current status of the ongoing BEPT experiment.

벤토나이트 완충재는 공학적방벽재 중 하나로 고준위방사성폐기물의 안전한 처분을 위해 매우 중요한 기능을 수행한다. 특정 지하수 조건에 의해 벤토나이트에 침식 혹은 파이핑 현상이 발생할 수 있으며, 이는 공학적방벽의 전반적인 안전성에 영향을 미친다. 이와 관련된 국내 선행 연구는 모두 실험실 규모에서 수행되었기 때문에, 그 결과의 유용함에도 불구하고 일정 부분 한계를 지닌다. 따라서 한국원자력연구원은 BEPT(Bentonite Erosion and Piping Test)를 계획하여 현장 조건으로의 확장 및 실증 연구를 수행할 계획이다. 자세한 실험 설계에 앞서, 처분 관련 기술 선도국에서 수행된 선행 연구를 수집하여 분석하였다. 적합 실험 부지, 시스템 설계 등을 분석하여 BEPT 상세 설계 시 반영하였다. 본 기술보고는 조사한 해외 사례와 함께 현재 진행 중인 BEPT 실험 현황을 소개하기 위해 작성되었다.

Keywords

Acknowledgement

본 연구는 과학기술정보통신부의 재원으로 사용후핵연료관리핵심기술개발사업단 (2021M2E1A1085193)의 지원을 받아 수행되었습니다.

References

  1. Aoyagi, K., and Ishii, E., 2019, A method for estimating the highest potential hydraulic conductivity in the excavation damaged zone in mudstone. Rock Mechanics and Rock Engineering, 52, 385-401.
  2. Fransson, A., Akesson, M., and Andersson, L., 2017, Bentonite rock interaction experiment characterization of rock and intstallation, hydration and dismantling of bentontie parcels. SKB Report R-14-11, Stockholm, Sweden
  3. GTS, The CFM experiment, 2024.1.22. accessed, https://grimsel.com/gts-projects/cfm-section/cfm-introduction
  4. Hanamuro, T. (ed.), 2016, Horonebe Underground Research Laboratory project investigation report for the 2015 fiscal year. JAEA Review 2016-022, JAEA, Tokai, Japan. (In Japanese)
  5. Hong, C.H., Kim, J.W., Kim, J.S., and Lee, C., 2022, Review of erosion and piping in compacted bentonite buffers considering buffer-rock interactions and deduction of influencing factors. Tunnel and Underground Space, 32(1), 30-58.
  6. iKSNF, 2022, A Report of the Experimental results for the Interaction between Buffer and Near-field Rock Discontinuity in the Disposal System. iKSNF-SD2/1-22-SCR-03, iKSNF, Daejeon, Korea.
  7. iKSNF, 2023, A Report of the Experimental Database for the Interaction between Buffer and Near-field Rock Discontinuity in the Disposal System depending on Buffer Characteristics. iKSNF-SD2/1-23-SCR-04, iKSNF, Daejeon, Korea.
  8. Jo., M., Ono, M., Nakayama, M., Asano, H., and Ishii, T., 2019, A study of methods to prevent piping and erosion in buffer materials intended for a vertical deposition hole at the Horonobe Underground Research Laboratory. In: Norris, S., Neeft, E.A.C., and Van Geet, M. (eds) Multiple Roles of Clay in Radioactive Waste Confinement. Geological Society, London, p. 482.
  9. KAERI, 2005, A study on the erosion of bentonite buffer material of the engineered barrier system. KAERI/TR-3016/2005, KAERI, Daejeon, Korea.
  10. KAERI, 2021, Review of experimental design of erosion/piping processes in bentonite buffer materials considering buffer-rock interactions. KAERI/TR-8980/2021, KAERI, Daejeon, Korea.
  11. KAERI, 2024, Report on the site selection and characterization for BEPT(Bentonite Erosion and Piping Test), KAERI/TR-10345-2024, KAERI, Daejeon, Korea.
  12. Lanyon, B., Schneeberger, R., and Blechschmidt, 2018, In-rock bentonite erosion test(I-BET): site selection and bentonite source. Nagra arbeitsbericht NAB 18-29, Wettingen, Switzerland.
  13. Lee, C., Yoon, S., Cho, W.J., Jo, Y., Lee, S., Jeon, S., and Kim, G.Y., 2019, Study on thermal, hyrdaulic, and mechanical properties of KURT granite and Gyeongju bentonite. Journal of Nuclear Fuel Cycle Waste Technology, 17, 65-80.
  14. Lee, S.H., Kim, J.S., Kim, B.J., Lee, J.K., Lee, S.Y., and Kwon, J.S., 2022, International joint research for the colloid formation and migration in Grimsel test site: current status and perspectives. Journal of Nuclear Fuel Cycle and Waste Technology, 20(4), 455-468.
  15. Lee, S.M., Kim, H.S., and Na, K.C., 1980, Explanatory text of the geological map of Daejeon. KIGAM, Daejeon, Korea.
  16. Lloret, A., and Villar, M.V., 2007, Advances on the knowledge of the thermal-hydro-mechanical behavior of heavily compacted "FEBEX" bentonite. Physics and Chemistry of the Earth, Parts A/B/C, 32(8-14), 701-715.
  17. Martinez-Landa, L., and Carrera, J., 2005, An analysis of hydraulic conductivity scale effect in granite(Full-scale Engineered Barrier Experiment(FEBEX), Grimsel, Switzerland. Water Resources Research, 41(3), 1-13.
  18. Park, H.I., Lee, J.D., and Cheong, J.G., 1977, Explanatory text of the geological map of Yuseong. KIGAM, Daejeon, Korea.
  19. Schlickenrieder, L., Lanyon, G.W., Kontar, K., and Blechschmidt, I., 2017, Colloid formation and migration project: site instrumentation and initiation of the long-term in-situ test. Nagra technical report, NTB 15-03, Wettingen, Switzerland.