Journal of the Korean Geotechnical Society (한국지반공학회논문집)

Korean Geotechnical Society (한국지반공학회)
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Development of Thermomechanical Coupled Numerical Model for Energy Slab

에너지 슬래브의 열-역학적 수치해석 모델 개발

  • Park, Sangwoo (Dept. of Civil Engrg. and Environmental Sciences, Korea Military Academy) ;
  • Choi, Hangseok (School of Civil, Environmental and Architectural Engrg., Korea Univ.) ;
  • Lee, Seokjae (Dept. of Civil Engrg., Kunsan National Univ.)
  • 박상우 (육군사관학교 토목환경학과) ;
  • 최항석 (고려대학교 건축사회환경공학부) ;
  • 이석재 (군산대학교 토목공학과)
  • Received : 2024.01.31
  • Accepted : 2024.02.08
  • Published : 2024.02.29
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Abstract

In this study, a thermomechanical numerical model was developed to evaluate the stability of energy slabs. First, a wall-type energy slab was installed in a residential underground parking lot, and thermal performance tests were conducted. Based on the tests, a numerical thermohydraulics model of the energy slab was developed to accurately simulate the thermal behavior in thermal performance tests. Finally, utilizing the temperature data acquired using the developed model, a thermomechanical numerical model of the energy slab was established. The thermomechanical model was then used to simulate the thermal stresses induced by operating the energy slab. The results demonstrated a maximum thermal stress of 5,300 kPa, which highlights the need to utilize cement mortar with sufficient tensile strength to realize stable operation of the energy slab.

본 연구에서는 에너지 슬래브의 안정성을 검토하기 위해 열-역학적 수치해석 모델을 개발하였다. 먼저, 주거용 건물 지하주차장에 벽체형 에너지 슬래브를 설치한 뒤 현장 열성능 평가시험(Thermal performance test, TPT)을 수행하였다. 이를 기반으로 현장 열성능 평가시험의 열-수리학적 거동을 정교하게 모사할 수 있는 에너지 슬래브의 열-수리학적 수치해석 모델을 개발하였다. 마지막으로, 열-수리학적 모델을 통해 도출된 시간-온도 데이터를 기반으로 에너지 슬래브의 열-역학적 수치해석 모델을 개발하였다. 개발된 모델을 기반으로 에너지 슬래브의 운용에 따른 열응력을 산정한 결과 최대 5,300kPa의 열응력이 발생하였으며, 이는 에너지 슬래브의 안정적인 운용을 위해 충분한 인장강도가 확보된 시멘트 몰탈 활용이 필요하다는 것을 시사한다.

Keywords

Acknowledgement

본 연구는 2023년도 군산대학교 신임교수 연구비 지원 및 교육부의 재원으로 한국연구재단의 지원을 받아 수행된 지자체-대학 협력기반 지역혁신 사업의 결과입니다(2023RIS-008).

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