Journal of Korean Society of Coastal and Ocean Engineers (한국해안·해양공학회논문집)

Korean Society of Coastal and Ocean Engineers (한국해안·해양공학회)
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Prediction of Wave Force on a Long Structure of Semi-infinite Breakwater Type Considering Diffraction

회절을 고려한 반무한방파제 형식의 장대구조물에 작용하는 파력 예측

  • Jung, Jae-Sang (Rural Research Institute, Korea Rural Community Corporation) ;
  • Lee, Changhoon (Department of Civil and Environmental Engineering, Sejong University) ;
  • Cho, Yong-Sik (Department of Civil and Environmental Engineering, Hanyang University)
  • 정재상 (한국농어촌공사 농어촌연구원) ;
  • 이창훈 (세종대학교 건설환경공학과) ;
  • 조용식 (한양대학교 건설환경공학과)
  • Received : 2015.09.03
  • Accepted : 2015.12.02
  • Published : 2015.12.31
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Abstract

In this study, the wave force distribution acting on a semi-infinite and vertical-type long structure is investigated considering diffraction. An analytical solution of the wave force acting on long structures is also suggested in this study. The wave forces on long structures are evaluated for monochromatic, uni-directional random, and multi-directional random waves. Diffraction effects in front of the breakwater and on the lee side of the breakwater are considered. The wave force on a long structure becomes zero when the relative length of the breakwater (1/L) is zero. The diffraction effects are relatively strong when the relative length of the breakwater is less than 1.0, and the wave forces decrease greatly for long structure when the relative length of the breakwater is larger than 0.5. Therefore, it is necessary to consider diffraction effects when the relative length of the breakwater is less than 1.0, and the relative length of the breakwater must be at least 0.5 in order to obtain a reduction of wave force on long structures.

본 연구에서는 회절을 고려하여 반무한방파제 형식의 직립식 장대구조물에 작용하는 파력에 대해 검토하였다. 장대구조물에 작용하는 파력은 규칙파, 일방향 불규칙파 및 다방향 불규칙파를 대상으로 하였다. 방파제 전면 및 후면에서 발생하는 회절을 모두 고려하였다. 방파제의 상대길이(1/L)가 0인 경우 방파제에 작용하는 파력은 회절에 의해 0이 된다. 방파제의 상대길이가 1.0 이하인 경우에는 회절의 영향이 비교적 강하였으며, 방파제의 상대길이가 0.5 이상인 경우에는 방파제의 장대화 효과에 의해 작용 파력이 크게 감소하였다. 즉, 방파제의 상대길이가 1.0 이하인 경우에는 회절효과의 고려가 필요하며, 장대 방파제의 파력 감소효과를 얻기 위해서는 방파제의 상대길이가 최소 0.5 이상이어야 함을 알 수 있다.

Keywords

References

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Cited by

  1. Proposal of Sliding Stability Assessment Formulas for an Interlocking Caisson Breakwater under Wave Forces vol.29, pp.2, 2017, https://doi.org/10.9765/KSCOE.2017.29.2.77
  2. Distribution of Wave Forces at Points on a Vertical Structure of Semi-Infinite Breakwater Considering Diffraction vol.28, pp.4, 2016, https://doi.org/10.9765/KSCOE.2016.28.4.240