Journal of Wind Energy (풍력에너지저널)

Korea Wind Energy Association (한국풍력에너지학회)
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Nonlinear Structural Analysis of Embedded Ring Foundations for Partial Repowering of Aging Onshore Wind Turbines

노후 육상풍력터빈의 부분적 리파워링을 위한 강관 매입형 확대기초의 비선형 구조해석

  • 송성훈 (한국건설기술연구원, 인프라안전연구본부) ;
  • 정연주 (한국건설기술연구원, 인프라안전연구본부) ;
  • 박민수 (한국건설기술연구원, 인프라안전연구본부) ;
  • 김정수 (한국건설기술연구원, 인프라안전연구본부)
  • Received : 2019.10.30
  • Accepted : 2019.12.09
  • Published : 2019.12.31
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Abstract

In order to reuse the support structures of aging wind turbines, the structural integrity of pedestals that transfer loads from a tower to a support structure must be properly evaluated. In this study, a numerical analysis model of embedded ring foundations was established by analyzing the failure cases and integrity evaluation cases of embedded ring foundations, which were widely applied to onshore wind farms in Korea. In addition, nonlinear structural analysis was carried out to analyze the effects of (a) boundary conditions, (b) concrete material properties, (c) the presence or absence of rebars, and (d) the shear stiffness of radial rebars through a steel ring. As a result of the analysis, (1) the boundary condition has the greatest effect on the structural behavior and the effective area of the foundation. (2) Due to the low stress state of concrete, the effect of concrete material properties on ultimate strength is insignificant. (3) When the compressive strength of concrete is larger than the ultimate strength, the effect of rebars on structural behavior and load resistance capacity is insignificant. (4) The dowel action of the radial rebar has a relatively large effect on concrete stress.

Keywords

Acknowledgement

본 연구는 산업통상자원부(한국에너지기술평가원)의 "노후 풍력발전단지의 가용성 향상을 위한 리파워링 전주기 기술 개발(과제번호 201830100254110)" 과제의 일환으로 수행되었으며 이에 감사드립니다.

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