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

Korean Society of Coastal and Ocean Engineers (한국해안·해양공학회)
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Stability Number of Additionally Placed Armor Unit (Tetrapod) Covered on Existing Two-Layered Tetrapod Rubble Mound Structures: Pattern Placing Condition

기존 2층 피복 테트라포드 상부에 추가 거치되는 피복재(테트라포드)의 안정계수: 정적거치 조건

  • Kim, Young-Taek (Department of Land, Water and Environment Research, Korea Institute of Civil Engineering and Building Technology) ;
  • Lee, Jong-In (Department of Civil Engineering, Chonnam National University)
  • 김영택 (한국건설기술연구원 국토보전연구본부) ;
  • 이종인 (전남대학교 공과대학 토목공학과)
  • Received : 2020.11.23
  • Accepted : 2020.12.15
  • Published : 2020.12.31
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Abstract

Since the aging of coastal structures have been increased, the researches about the reinforcements of the existing aged structures are needed. Especially, the existing armor units placed on rubble mound structures should satisfy the stability against the increased design wave conditions. However the researches about these design problems have not been performed. In this study, the hydraulic model tests to investigate the stability number about the additionally placed armor unit were conducted. The main armor unit is a Tetrapod. The test results showed that the stability number (Kd) for additionally placed armor units(Tetrapod) increased up to maximum 10% comparing with that for 2 layers tetrapod (Kd = 8) within these test conditions with the pattern placing for existing armor layers and the stable armor layer slope for the non overtopping condition.

항만구조물의 노후화가 가속화되면서 상향된 설계파 조건에 대응하기 위한 연구가 필요한 상황이다. 특히 피복재가 거치되는 경사식구조물의 경우, 상향된 설계파고에 안정중량을 확보하기 위해서는 피복재의 중량 증가가 필요하다. 그렇지만 그와 관련된 연구는 진행된 사례가 없다. 본 연구에서는 기존 피복재가 거치된 경사식구조물에 추가 피복재를 거치하는 경우, 추가 피복재의 안정중량 산정을 위한 수리모형실험을 수행하였다. 피복재로는 콘크리트 이형블록인 테트라포드를 적용하였다. 실험결과에 의하면 비월파 조건에서 기존 피복재(테트라포드)가 정적 거치이고 사면경사의 변화가 거의 없는 경우 실험조건 내에서 추가피복재(테트라포드)의 안정계수(Kd)는 일반적인 테트라포드 안정계수(Kd = 8)에 비하여 주기별로 차이가 있으나 최대 10% 증가하는 것으로 나타났다.

Keywords

References

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