Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT) (방사성폐기물학회지)

Korean Radioactive Waste Society (한국방사성폐기물학회)
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Identification of Mechanical Parameters of Kyeongju Bentonite Based on Artificial Neural Network Technique

  • Received : 2022.05.30
  • Accepted : 2022.07.06
  • Published : 2022.09.30
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Abstract

The buffer is a critical barrier component in an engineered barrier system, and its purpose is to prevent potential radionuclides from leaking out from a damaged canister by filling the void in the repository. No experimental parameters exist that can describe the buffer expansion phenomenon when Kyeongju bentonite, which is a buffer candidate material available in Korea, is exposed to groundwater. As conventional experiments to determine these parameters are time consuming and complicated, simple swelling pressure tests, numerical modeling, and machine learning are used in this study to obtain the parameters required to establish a numerical model that can simulate swelling. Swelling tests conducted using Kyeongju bentonite are emulated using the COMSOL Multiphysics numerical analysis tool. Relationships between the swelling phenomenon and mechanical parameters are determined via an artificial neural network. Subsequently, by inputting the swelling tests results into the network, the values for the mechanical parameters of Kyeongju bentonite are obtained. Sensitivity analysis is performed to identify the influential parameters. Results of the numerical analysis based on the identified mechanical parameters are consistent with the experimental values.

Keywords

Acknowledgement

This work was supported by the Nuclear Research and Development Program of the National Research Foundation of Korea (NRF) (2021M2E3A2041351) and the National Research Foundation of Korea Basic Research Project (2020R1A2B5B01002067) funded by the Korea government (Ministry of Science and ICT, MSIT).

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