Journal of the Earthquake Engineering Society of Korea (한국지진공학회논문집)

Earthquake Engineering Society of Korea (한국지진공학회)
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Analysis of Three-dimensional Earthquake Responses of a Floating Offshores Structure with an Axisymmetric Floating Structure

축대칭 부유구조물을 가지는 부유식 해양구조물의 3차원 지진응답 해석기법 개발

  • Lee, Jin Ho (Korea Railroad Research Institute, Maglev Train Research Team) ;
  • Kim, Jae Kwan (Seoul National University, Department Civil and Environmental Engineering)
  • 이진호 (한국철도기술연구원 자기부상철도연구팀) ;
  • 김재관 (서울대학교 건설환경공학부)
  • Received : 2015.03.24
  • Accepted : 2015.05.18
  • Published : 2015.07.01
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Abstract

A seismic response analysis method for three-dimensional floating offshore structures due to seaquakes is developed. The hydrodynamic pressure exerted on the structure is calculated taking into account the compressibility of the sea water, the fluid-structure interaction, the energy absorption by the seabed, and the energy radiation into infinity. To validate developed method, the hydrodynamic pressure induced by the vibration of a floating massless rigid circular disk is calculated and compared with an exact analytical solution. The developed method is applied to seismic analysis of a support structure for a floating offshore wind turbine subjected to the hydrodynamic pressures induced from a seaquake. Analysis results show that earthquake response of a floating offshore structure can be greatly influenced by the compressibility of fluid, the depth (natural frequencies) of the fluid domain, and the energy absorption capacity of the seabed.

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