Ocean Systems Engineering

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Numerical analysis of an offshore platform with large partial porous cylindrical members due to wave forces

  • Park, Min-Su (Institute of Ocean Energy, Saga University) ;
  • Kawano, Kenji (Department of Ocean and Civil Engineering, Kagoshima University) ;
  • Nagata, Shuichi (Institute of Ocean Energy, Saga University)
  • Received : 2011.09.14
  • Accepted : 2011.12.09
  • Published : 2011.12.25
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Abstract

In the present study, an offshore platform having large partial porous cylindrical members, which are composed of permeable and impermeable cylinders, is suggested. In order to calculate the wave force on large partial porous cylindrical members, the fluid domain is divided into three regions: a single exterior region, N inner regions and N beneath regions, and the scattering wave in each fluid region is expressed by an Eigen-function expansion method. Applying Darcy's law to the porous boundary condition, the effect of porosity is simplified. Wave excitation forces and wave run up on the structures are presented for various wave conditions. For the idealized three-dimensional platform having large partial porous cylindrical members, the dynamic response evaluations of the platform due to wave forces are carried out through the modal analysis. In order to examine the effects of soil-structure interaction, the substructure method is also applied. The displacement and bending stress at the selective nodal points of the structure are computed using various input parameters, such as the shear-wave velocity of soil, the wave height and the wave period. Applying the Monte Carlo Simulation (MCS) method, the reliability evaluations at critical structure members, which contained uncertainties caused by dynamic forces and structural properties, are examined by the reliability index with the results obtained from MCS.

Keywords

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Cited by

  1. Mathematical Modeling of Partial-Porous Circular Cylinders with Water Waves vol.2015, 2015, https://doi.org/10.1155/2015/903748