Estimating design wave for offshore structures in Italian waters

This paper describes a methodology for estimating the design wave parameters for offshore structures. For the estimation of the design wave height the concept of an equivalent triangular storm is discussed. It is shown how it overcomes the limitations of previous methodologies. For the estimation of the wave period a quasi-deterministic theory is applied. A description is given of the simple method proposed, which requires only the estimation of the significant wave height of the sea state in which the highest wave in the return period of the design wave will occur with the highest probability. Final discussions address examples of the estimation of design wave data to determine the size of offshore structures to be built along the coasts of Italy, the Pacific and Atlantic Oceans and Gulf of Alaska, using wave data gathered from instruments managed by the Environment and Territory Agency and the National Data Buoy Centre.

[1]  A general theory of three-dimensional wave groups Part I: The formal derivation , 1997 .

[2]  M. Longuet-Higgins.  On the joint distribution of wave periods and amplitudes in a random wave field , 1983, Proceedings of the Royal Society of London. A. Mathematical and Physical Sciences.

[3]  Sverre Haver,et al.  Wave climate off northern Norway , 1985 .

[4]  C. Soares,et al.  Statistical Uncertainty in Long-Term Distributions of Significant Wave Height , 1996 .

[5]  C. Guedes Soares,et al.  Modelling uncertainty in long-term predictions of significant wave height , 2001 .

[6]  M. J. Tucker.  An improved ‘Battjes’ method for predicting the probability of extreme waves , 1989 .

[7]  Paolo Boccotti,et al.  Relations between characteristic sea wave parameters , 1982 .

[8]  M. S. Longuet-Higgins,et al.  On the distribution of the heights of sea waves: Some effects of nonlinearity and finite band width , 1980 .

[9]  Harald E. Krogstad,et al.  Height and period distributions of extreme waves , 1985 .

[10]  G. Forristall.  The Distribution of Measured and Simulated Wave Heights as a Function of , 1984 .

[11]  W. Pierson,et al.  A proposed spectral form for fully developed wind seas based on the similarity theory of S , 1964 .

[12]  M. Longuet-Higgins.  On the joint distribution of the periods and amplitudes of sea waves , 1975 .

[13]  C. Guedes Soares,et al.  Modelling the long-term distribution of significant wave height with the Beta and Gamma models , 1999 .

[14]  C. Guedes Soares,et al.  ASSESSMENT OF THE UNCERTAINTY IN VISUAL OBSERVATIONS OF WAVE HEIGHT , 1986 .

[15]  G. Forristall.  Wave Crest Distributions: Observations and Second-Order Theory , 2000 .