This study presents a new statistical cubicization approach for predicting the stochastic response of offshore platforms subjected to a Morison-type nonlinear drag loading. Statistics of the original system are obtained from an equivalent nonlinear system, which is constructed by replacing the Morison drag force by a cubic polynomial function of the relative fluid-structure velocity, up to cubic order: A Volterra series expansion with a finite Fourier series representation is used to approximate the response of the equivalent system. Exact solutions are developed to express the Fourier coefficients of the second and third-order response as functions of the Fourier coefficients of the first-order relative fluid-structure velocity. Response statistics are then computed by ensemble averaging over a suitable number of realizations of the first-order Gaussian response. Response statistics up to the sixth order, computed for a variety of sea conditions, show accuracy and efficiency of the proposed method as compared to digital simulation
Titolo: | Stochastic response of offshore structures by a new approach to statistical cubicization |
Autori: | FAILLA, Giuseppe (Corresponding) |
Data di pubblicazione: | 2002 |
Rivista: | |
Handle: | http://hdl.handle.net/20.500.12318/7572 |
Appare nelle tipologie: | 1.1 Articolo in rivista |