Journal of the Korean GEO-environmental Society (한국지반환경공학회 논문집)

Korean Geo-Environmental Society (한국지반환경공학회)
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Effects of Pile Diameter on the Lateral Behavior of Offshore Pile in the Southwestern Area of Korea

서남해안 해상풍력단지 말뚝의 직경에 따른 횡방향 거동

  • Lee, In (Hongik University Department of Civil Engineering) ;
  • Choi, Younggyun (Hongik University Department of Civil Engineering) ;
  • Kim, Honglak (Hongik University Department of Civil Engineering) ;
  • Kwon, Osoon (Principal Research Scientist KIOST Coastal Development & Ocean Energy Research Division) ;
  • Youn, Heejung (Hongik University Department of Civil Engineering)
  • Published : 2013.05.01
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Abstract

This paper presents the effect of pile diameter on the lateral behavior of offshore pile for wind turbine. The material parameters of the soils were estimated through SPT on the Southwestern offshore area in Korea, where the first wind farm is planned. The FDM software, FLAC3D, and LPile were adopted to derive the load-displacement curve, p-y curve, and maximum bending moment at a specified displacement. It was found that the results from softwares significantly differ and the LPile could overestimate the allowable capacity. The maximum bending moment along the pile with 2m diameter could be as large as four times the bending moment with 1m diameter. Similar trend was observed for the allowable lateral capacity.

이 논문에서는 풍력터빈의 기초로 쓰이는 해상말뚝의 횡방향 거동에 대한 말뚝 직경의 영향에 관하여 분석하였다. 지반의 물성값들은 국내 최초로 해상풍력단지 건립 예정후보지인 서남해안의 표준관입시험과 실내시험자료를 이용하였다. 유한차분해석프로그램(FLAC3D)과 p-y해석프로그램(LPile)을 사용하여 말뚝 두부의 하중-변위관계, 지반의 p-y 곡선, 말뚝에 발생하는 최대 휨모멘트 등을 말뚝의 직경에 따라 국내 외 허용변위기준을 적용하여 구하였다. 연구 결과 두 프로그램의 결과가 서로 다르게 나타났으며, LPile의 해석결과가 수평허용지지력을 과하게 나타냈다. 직경 2m의 말뚝에서 발생하는 최대 휨모멘트는 직경 1m의 말뚝에 발생하는 최대 휨모멘트보다 약 4배가량 크게 나타났으며, 수평허용지지력에서도 비슷한 경향을 보였다.

Keywords

References

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