Numerical Analysis of Laboratory Heating Experiment on Granite Specimen

Dong-Joon Youn; Changlun Sun; Zhuang Li

doi:10.7474/TUS.2022.32.6.558

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2022 Vol.32, Issue 6 Preview Page Next Page

Original Article

Numerical Analysis of Laboratory Heating Experiment on Granite Specimen 화강암의 실내 가열실험에 대한 수치해석적 검토

31 December 2022. pp. 558-567

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Abstract

The evolution of temperature and thermal stress in a granite specimen is studied via heating experiment in the context of a high-level radioactive waste repository. A heating condition based on the decay-induced heat is applied to a cubic granite specimen to measure the temperature and stress distributions and their evolution over time. The temperature increases quickly due to heat conduction along the heated surfaces, but a significant amount of thermal energy is also lost through other surfaces due to air convection and conduction into the loading machine. A three-dimensional finite element-based model is used to numerically reproduce the experiment, and the thermo-mechanical coupling behavior and modeling conditions are validated with the comparison to the experimental results. The most crucial factors influencing the heating experiment are analyzed and summarized in this paper for future works.

Keywords

Granite

Heating

Thermal expansion

Thermo-mechanical coupling behavior

Radioactive waste disposal

고준위방사성폐기물의 지중저장 안정성 평가의 일환으로 가열 중인 화강암의 온도변화와 열응력 발생 양상을 파악하기 위하여 가열실험을 실시하였다. 폐기물의 붕괴열 발생조건을 가정하고 정육면체 형태의 화강암 시편에 적용하여 온도와 변위의 분포를 측정하였다. 시편의 온도는 가열봉에서 발생하는 전도로 인하여 즉각적으로 상승하지만 동시에 외기에 노출되거나 하중재하장치에 접촉되어 있는 표면을 통하여 상당한 양의 열에너지가 소산되었다. 해당 실험에 대한 분석과 이해를 위해 실험조건을 삼차원 유한요소 수치해석으로 재구현하였다. 실험에서 관찰된 열-역학 연계 현상과 주변조건의 변화를 해석에 적용하고 이를 실내실험 결과와 비교하여 검증하였다. 이를 통해 가열실험에 영향을 주는 인자들을 분석하고 향후 관련 연구에서 고려되어야 할 부분을 요약하였다.

키워드

화강암

가열

열팽창

열-역학 연계 거동

고준위방사성폐기물처분장

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Information

Publisher :Korean Society for Rock Mechanics and Rock Engineering
Publisher(Ko) :한국암반공학회
Journal Title :Tunnel and Underground Space
Journal Title(Ko) :터널과 지하공간
Volume : 32
No :6
Pages :558-567
Received Date : 2022-12-16
Revised Date : 2022-12-28
Accepted Date : 2022-12-28
DOI :https://doi.org/10.7474/TUS.2022.32.6.558

Tunnel and Underground Space ISSN:1225-1275(Print) 2287-1748(Online) 터널과 지하공간

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