Stochastic hydroelastic analysis of pontoon-type very large floating structures considering directional wave spectrum

► We derive the transfer matrices for stochastic hydroelastic analysis of VLFS.
► We model the irregular wind waves by the directional wave spectrum.
► The fluid–structure interaction is resolved applying the modal expansion method.
► The influence of the mean wave angle on the stochastic response is investigated.

The hydroelastic response of pontoon-type very large floating structures (VLFS) is obtained by resolving the interaction between the surface waves and the floating elastic body. We carry out the analysis in the frequency domain, assuming that the surface waves can be described by a directional wave spectrum. The response spectra can then be computed by application of stationary random vibration analysis. Applying the modal expansion method, we obtain a discrete representation of the required transfer matrices for a finite number of frequencies, while the influence of the wave direction is obtained by numerical integration of the directional components of the spectrum. Moreover, assuming a Gaussian input, we can apply well known approximations to obtain the distribution of extremes. The method is applied to an example VLFS and the effect of different mean wave angles on the stochastic response is investigated.