Journal of the Earthquake Engineering Society of Korea (한국지진공학회논문집)

Earthquake Engineering Society of Korea (한국지진공학회)
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Analysis of Earthquake Responses of a Floating Offshore Structure Subjected to a Vertical Ground Motion

해저지진의 수직지반운동에 의한 부유식 해양구조물의 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) ;
  • Jin, Byeong Moo (Daewoo E&C, Institute of Construction Technology, Civil Engineering Research Team)
  • 이진호 (한국철도기술연구원 자기부상철도연구팀) ;
  • 김재관 (서울대학교 건설환경공학부) ;
  • 진병무 ((주)대우건설 기술연구원 토목연구팀)
  • Received : 2014.05.12
  • Accepted : 2014.10.01
  • Published : 2014.11.01
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Abstract

Considering a rigorously fluid-structure interaction, a method for an earthquake response analysis of a floating offshore structure subjected to vertical ground motion from a seaquake is developed. Mass, damping, stiffness, and hydrostatic stiffness matrices of the floating offshore structure are obtained from a finite-element model. The sea water is assumed to be a compressible, nonviscous, ideal fluid. Hydrodynamic pressure, which is applied to the structure, from the sea water is assessed using its finite elements and transmitting boundary. Considering the fluid-structure interaction, added mass and force from the hydrodynamic pressure is obtained, which will be combined with the numerical model for the structure. Hydrodynamic pressure in a free field subjected to vertical ground motion and due to harmonic vibration of a floating massless rigid circular plate are calculated and compared with analytical solutions for verification. Using the developed method, the earthquake responses of a floating offshore structure subjected to a vertical ground motion from the seaquake is obtained. It is concluded that the earthquake responses of a floating offshore structure to vertical ground motion is severely influenced by the compressibility of sea water.

Keywords

References

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Cited by

  1. Analysis of Three-dimensional Earthquake Responses of a Floating Offshores Structure with an Axisymmetric Floating Structure vol.19, pp.4, 2015, https://doi.org/10.5000/EESK.2015.19.4.145