A Method to Predict Stress Intensity Factor of Surface Crack at Weld Toe of Offshore Structures under Wave Loads

Abstract:

The calculation of stress intensity factor (SIF) in fracture mechanics-based fatigue life prediction is mainly based on empirical formulas, the poor applicability of which limits the wide application of fatigue assessment based on crack propagation. This paper proposed a SIF calculation method for structures under wave loads. It was proved correct by comparing with the empirical formulas. Then, the method proposed was applied for the surface crack at weld toe of a connection between the column and brace of a semi-submersible platform. The predicted results showed that SIF ranges varied with wave loads, which were subjected to the effects of wave directions and frequencies. In addition, SIF ranges calculated by empirical formulas were very different from those of the proposed method. In order to accurately predict fatigue crack propagation life for ocean engineering structures, it is necessary to take the characters of wave loads into consideration. The proposed method in this paper may provide a reference.

• Periodical: Advanced Materials Research (Volume 978)
• Pages: 118-122
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.978.118
• Online since: June 2014
• Authors: Xiao Shun Yan*, Xiao Ping Huang
• Keywords: Fatigue Crack Propagation, Semi-Elliptical Surface Crack, Semi-Submersible Platform, Stress Intensity Factor (SIF), Wave-Induced Load

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