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Proposal of Sliding Stability Assessment Formulas for an Interlocking Caisson Breakwater under Wave Forces

파랑하중에 대한 인터로킹 케이슨 방파제의 미끌림 안정성 평가식 제안

  • Park, Woo-Sun (Coastal Engineering Division, Korea Institute of Ocean Science and Technology) ;
  • Won, Deokhee (Coastal Engineering Division, Korea Institute of Ocean Science and Technology) ;
  • Seo, Jihye (Coastal Engineering Division, Korea Institute of Ocean Science and Technology)
  • 박우선 (한국해양과학기술원 연안공학연구본부) ;
  • 원덕희 (한국해양과학기술원 연안공학연구본부) ;
  • 서지혜 (한국해양과학기술원 연안공학연구본부)
  • Received : 2017.04.06
  • Accepted : 2017.04.17
  • Published : 2017.04.30

Abstract

Recently, the possibility of abnormal waves of which height is greater than design wave height have been increased due to the climate change, and therefore it has been urgent to secure the stability for harbor structures. As a countermeasure for improving the stability of conventional caisson breakwaters, a method has been proposed in which adjacent caissons are interlocked with each other to consecutively resist the abnormal wave forces. In order to reflect this research trend, the reduction effect of the maximum wave force resulted from introducing a long caisson has been presented in the revision to the design criteria for ports and fishing harbors and commentary. However, no method has been proposed to evaluate the stability of interlocking caisson breakwater. In this study, we consider the effect of the phase difference of the oblique incidence of the wave based on the linear wave theory and apply the Goda pressure formula for considering design wave pressure distribution in the vertical direction. Sliding stability assessment formula of an interlocking caisson breakwater is proposed for regular, irregular, and multi-directional irregular wave conditions.

기후변화에 따른 설계파고를 초과하는 이상파랑의 내습 가능성이 커지면서 항만구조물의 안정성 확보가 시급한 실정이다. 이러한 변화에 능동적으로 대응하기 위하여 기존 방파제에 대한 평가기준과 신설 장대형 방파제의 설계기준이 점차 강화되면서 인터로킹 케이슨 방파제에 대한 관심이 대두되고 있다. 하지만 현재까지는 항만 및 어항 설계기준 해설[부록] 개정안에 장대형 케이슨에 발생하는 파력 평활화 효과가 제시되어있을 뿐 인터로킹 케이슨 방파제의 안정성을 평가하기 위한 방법이 별도로 제시되어 있지 않다. 이에, 본 연구에서는 선형파 이론에 기초하여 경사 입사하는 파랑의 작용 위치별 위상차의 효과를 고려하고, 최대 파력분포는 설계기준의 Goda 파압식을 적용하여, 규칙파, 불규칙파 및 다방향 불규칙파에 대한 인터로킹 케이슨 방파제의 미끌림 안정성 평가식을 제안하였다.

Keywords

References

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