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**Vibration of an offshore structure having the form of a hollow column partially filled with multiple fluids and immersed in water.**
*(English)*
Zbl 1251.74036

Summary: This paper employs the numerical assembly method (NAM) to determine the exact frequency-response amplitudes of an offshore structure such as piles or towers having the form of a hollow column filled with multiple fluids, immersed in water, carrying an eccentric tip mass supported by a translational spring and/or a rotational spring, and subjected to a harmonic force. The hollow column is modeled as a Bernoulli-Euler cantilever beam fixed at the bottom. For the case of zero harmonic force, the simultaneous equations of the vibration system reduce to an eigenvalue problem so that the natural frequencies and mode shapes of the beam can also be obtained. The effect of height of filled fluids on the characteristics of free vibration is also presented.

### MSC:

74S30 | Other numerical methods in solid mechanics (MSC2010) |

74F10 | Fluid-solid interactions (including aero- and hydro-elasticity, porosity, etc.) |

74H45 | Vibrations in dynamical problems in solid mechanics |

74K10 | Rods (beams, columns, shafts, arches, rings, etc.) |

### Keywords:

Bernoulli-Euler cantilever beam
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\textit{H.-Y. Lin} et al., J. Appl. Math. 2012, Article ID 158983, 16 p. (2012; Zbl 1251.74036)

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### References:

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