KSCE Journal of Civil and Environmental Engineering Research (대한토목학회논문집)

Korean Society of Civil Engeneers (대한토목학회)
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An Experimental Study on Reinforcement Method for Reuse of Onshore Wind Turbine Spread Footing Foundations

육상풍력터빈 확대기초의 재사용을 위한 보강방법에 관한 실험적 연구

  • Song, Sung Hoon (Korea Institute of Civil Engineering and Building Technology) ;
  • Jeong, Youn Ju (Korea Institute of Civil Engineering and Building Technology) ;
  • Park, Min Su (Korea Institute of Civil Engineering and Building Technology) ;
  • Kim, Jeong Soo (Korea Institute of Civil Engineering and Building Technology)
  • 송성훈 (한국건설기술연구원 인프라안전연구본부) ;
  • 정연주 (한국건설기술연구원 인프라안전연구본부) ;
  • 박민수 (한국건설기술연구원 인프라안전연구본부) ;
  • 김정수 (한국건설기술연구원 스마트건설혁신본부 국가BIM연구센터)
  • Received : 2020.03.20
  • Accepted : 2020.09.26
  • Published : 2021.02.01
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Abstract

In order to reuse existing onshore turbine foundations, it is important to redesign and reinforce the existing foundations according to the upgraded tower diameter and turbine load. In the present study, a slab extension reinforcement method and structure details of an anchorage part were examined in consideration of the reuse of spread footings, which are the most widely used foundation type in onshore wind turbine foundations. Experiments were conducted to evaluate the load resistance performance of a reinforced spread footing according to structure details of an anchorage part. The results showed that (1) the strength of an anchorage part could be increased by more than 30 % by adding reinforcement bars in the anchorage part, (2) pile-sleeves attached to an anchor ring contributed to an increase in rotational stiffness by preventing shear slip behavior between the anchor ring and the concrete, and (3) slab connectors contributed to an increase in the strength and deformation capacity by preventing the separation of new and old concrete slabs.

기존 육상풍력터빈의 리파워링 시 기존 기초를 재사용하기 위해서는 증가된 타워 직경 및 터빈 하중에 맞게 기존 기초를 재설계 및 보강하는 것이 중요하다. 본 연구에서는 육상풍력터빈의 기초형식 중 가장 널리 사용되고 있는 확대기초의 재사용을 위해 기존 확대기초 위에 새로운 콘크리트 기초부를 증설하는 슬래브 확장 보강방법 및 앵커부 구조디테일에 대해 검토하였다. 그리고 앵커부 구조디테일에 따른 보강된 확대기초의 하중저항성능을 실험적으로 평가하였다. 실험결과, (1) 앵커부 철근 유무에 따라 내력이 30 % 이상 증가하였다. (2) 앵커링에 부착된 Pile-sleeve는 앵커링과 콘크리트 사이의 전단슬립거동을 방지하여 회전강성 증가에 기여하였다. (3) Slab connector는 신?구 콘크리트 분리 방지 및 일체화 거동을 향상시켜 내력 및 변형능력 증가에 기여하였다.

Keywords

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