engleski

Nonlinear random wave load effects on offshore structures response

In this paper the authors developed an analytical procedure for predicting dynamic displacement response of fixed offshore structures to the action of random waves, representing the nonlinear drag force by cubic approximation. The structure is idealized as a linear one-degree of freedom system and a generalized co-ordinate system is chosen for assessing the structure"s properties, for which a suitable sinusoidal shape function is assumed. The spectra of the generalized load and of the generalized displacement response of fixed offshore structures, depending on an adequate basic arrangement of vertical cylindrical piles and the wave propagation angle, are defined by applying the spectral analysis method. Numerical example is included to demonstrate the potential of the analytical model and to quantify the effects of nonlinear drag force on the structural load and response.

ixed offshore structures; random waves; Morison"s equation

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