An improved procedure for generating standardised load-time histories for marine structures

作者:Li, Shanshan; Cui, Weicheng*; Paik, Jeom Kee
来源:Proceedings of the Institution of Mechanical Engineers - Part M: Journal of Engineering for the Maritime Environment , 2016, 230(2): 281-296.
DOI:10.1177/1475090215569818

摘要

The load sequence effect has been proved from laboratory tests to be an influencing factor that cannot be neglected in the fatigue analysis of marine structures. To take account of this significant factor, fatigue life prediction should be based on fatigue crack propagation theory rather than the currently used cumulative fatigue damage theory. Accordingly, fatigue loading needs to be provided as the load-time history in the time domain rather than the load spectrum in the frequency domain. A general procedure for generating the standardised load-time history for marine structures based on a short-term load measurement has been proposed by the authors. This article seeks to further improve on this procedure and explain how to apply the determined standardised load-time history in the fatigue life prediction method based on the fatigue crack propagation theory. Finally, generation and application of a standardised load-time history are given for a tubular T-joint of an offshore platform, which demonstrates the practical and effective use of the proposed approach.