Reliability Analysis of Offshore Structures with Consideration of Seasonal and Directional Effects

Abstract:

In the recent past an increasing number of failure events have been observed for offshore structures due to exceptional environmental loading conditions such as large waves. The occurrence of these failure events indicates a possible improvement in the traditional modeling of environmental characteristics, which are the basis for the load models for structural analysis and design. In this paper, the seasonal and directional effects in the modeling of the significant wave height for structural reliability analysis are studied. The peak over threshold (POT) method is selected to model the extremes in the non-stationary point process for the wave heights. The time-varying parameters are taken into account with a cyclic changing pattern to reflect the seasonal behavior. Both the extreme values and the storm occurrence rate are investigated in the different seasons. The results are utilized for the load characterization of offshore structures to investigate their sensitivity to the changing seasonal effects in reliability analyses. An example of selected structure is discussed.

• Periodical: Applied Mechanics and Materials (Volumes 578-579)
• Pages: 1459-1463
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.578-579.1459
• Online since: July 2014
• Authors: Chun Xue Song*, Yi Zhang, Ying Yi Cao
• Keywords: Climate Change, Extreme Value Distribution, Offshore Structures, Peak over Threshold Method, Point Process, Reliability Analysis, Significant Wave Height

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