A REVIEW OF THE PROBABILISTIC DESCRIPTION OF MORISON WAVE LOADING ANDRESPONSE OF FIXED OFFSHORE STRUCTURES

Offshore structures must be designed against failure resulting from bo th fatigue and high forces due to extreme environmental conditions. Th e common procedure is to expose the structure to a range of regular wa ves whose heights and periods are determined from the long-term probab ility distribution of the waveheights and their associated periods at the site. However, in reality these structures are exposed to random w ave-induced forces in the ocean environment, and hence it is inherentl y much more satisfactory to account for the randomness of the loading by establishing the probabilistic properties of the loading and the re sulting responses. The major obstacle is the nonlinearity of the drag component of Morison's wave loading which results in non-Gaussian dist ributions for both loading and response. In this paper, progress made to date towards a systematic probabilistic analysis of fixed jacket-ty pe offshore structures will be reviewed. (C) 1995 Academic Press Limit ed