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An Analytical Solution of Dynamic Responses for Seabed under Flow and Standing Wave Coexisting Fields

흐름과 완전중복파와의 공존장하에서 해저지반내 동적응답의 해석해

  • Lee, Kwang-Ho (Dept. of Energy Resources and Plant Eng., Catholic Kwandong Univ.) ;
  • Kim, Dong-Wook (Dept. of Civil and Environmental Eng., Korea Maritime and Ocean Univ.) ;
  • Kim, Do-Sam (Dept. of Civil Eng., Korea Maritime and Ocean Univ.) ;
  • Kim, Tae-Hyung (Dept. of Civil Eng., Korea Maritime and Ocean Univ.) ;
  • Kim, Kyu-Han (Dept. of Civil Eng., Catholic Kwandong Univ.) ;
  • Jeon, Jong-Hyeok (Dept. of Civil and Environmental Eng., Korea Maritime and Ocean Univ.)
  • 이광호 (가톨릭관동대학교 에너지자원플랜트공학과) ;
  • 김동욱 (한국해양대학교 토목환경공학과) ;
  • 김도삼 (한국해양대학교 건설공학과) ;
  • 김태형 (한국해양대학교 건설공학과) ;
  • 김규한 (가톨릭관동대학교 토목공학과) ;
  • 전종혁 (한국해양대학교 토목환경공학과)
  • Received : 2015.02.27
  • Accepted : 2015.04.15
  • Published : 2015.04.30

Abstract

An analytical solution of dynamic responses for seabed in shallow, finite and infinite thicknesses has been developed under flow and standing wave coexisting field at a constant water depth condition. To do this, based on the Biot's consolidation theory, the seabed is assumed as a porous elastic media with the assumptions that pore fluid is compressible and Darcy law governs the flow. The developed analytical solution is compared with the previous results and is verified. Using the analytical solution the deformation, pore pressure, effective and shear stresses of seabed are examined under various given values of flow velocity, incident wave period and seabed thickness. From this study, it is confirmed that the seabed response is quite different depending on consideration of flow, which causes changing period and length of incident and reflection waves.

일정수심상에서 완전중복파와 흐름이 공존하는 경우 얕은 두께를 포함하는 유한두께 및 무한두께의 해저 지반내에서 동적응답을 나타내는 해석해를 유도한다. 이 때, Biot의 압밀이론에 기초하여 해저지반은 투과탄성매체로, 간극유체는 압축성으로, 그리고 지반내 간극수의 흐름은 Darcy법칙으로 각각 가정된다. 도출된 해석해는 기존의 해석결과와의 비교 검토로부터 검증되며, 실제 계산에서는 흐름속도, 입사파의 주기 및 지반두께 등의 변화에 따른 지반변위, 간극수압, 유효응력 및 전단응력의 변동특성을 면밀히 검토한다. 이로부터 흐름이 존재하는 경우 흐름으로 인한 입사파와 반사파의 주기 및 파장의 변화로 인하여 흐름이 없는 경우의 지반응답과는 많은 차이를 나타낸다는 것을 확인할 수 있다.

Keywords

References

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Cited by

  1. An Analytical Study on Generation of Pore-Water Pressures Induced by Flow and Waves in Seabed, and Resulting Liquefaction vol.27, pp.5, 2015, https://doi.org/10.9765/KSCOE.2015.27.5.324
  2. An Analytical Solution of Dynamic Responses for Seabed under Coexisting Fields of Flow and Partial Standing Wave with Arbitrary Reflection Ratio vol.31, pp.6, 2015, https://doi.org/10.7843/kgs.2015.31.6.27