Journal of Korea Water Resources Association (한국수자원학회논문집)

Korea Water Resources Association (한국수자원학회)
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Calculation of the Peak-delay Force Reduction Parameter of Multi-Directional Random Waves Acting on a Long Caisson Breakwater

장대 케이슨 방파제에 작용하는 다방향 불규칙파랑의 파력감소계수 산정

  • 정재상 (한양대학교 일반대학원 건설환경공학과(한국농어촌공사 농어촌개발처)) ;
  • 김범형 (현대산업개발 토목사업본부) ;
  • 김형준 (한양대학교 일반대학원 건설환경공학과(한국건설기술연구원 하천.해안항만연구실)) ;
  • 조용식 (한양대학교 건설환경공학과)
  • Received : 2010.05.24
  • Accepted : 2010.08.30
  • Published : 2010.10.31
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Abstract

By employing multi-directional random waves, a parameter controlling the force acting on a long caisson breakwater is investigated in detail. Both JONSWAP (Joint North Sea Wave Project) and asymmetric directional spectra are adopted for frequency and directional spectra. It is found that the parameter decreases as the length of caisson and the angle of main direction of incident waves increase. Furthermore, the parameter is much similar to that of regular waves as the maximum spreading parameter $s_{max}$ increases. The parameter, however, decreases as asymmetry parameter ${\mu}$ increases when the main direction of incident waves is oblique to the breakwater.

다방향 불규칙파랑을 입사파랑으로 적용하여 장대 케이슨 방파제에 작용하는 파력감소계수에 대하여 연구하였다. 다방향 불규칙파랑의 주파수 및 방향 스펙트럼으로 JONSWAP (Joint North Sea Wave Project) 스펙트럼과 비대칭 방향 스펙트럼이 각각 적용되었다. 계산결과, 케이슨 방파제의 길이와 입사파랑 주파향의 입사각이 증가할수록 파력감소계수는 감소함을 알 수 있었다. 그리고 최대방향분포계수 $s_{max}$가 증가할수록 파력감소계수는 규칙파와 유사한 경향을 보였다. 다방향 불규칙파랑이 방파제에 비스듬히 입사할 경우 비대칭계수 ${\mu}$가 증가할수록 파력감소계수는 감소하였다.

Keywords

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