Confidence level and reliability analysis of the fatigue life of CFRP laminates predicted based on fracture fatigue entropy

This study provides a novel methodology to evaluate fatigue life with the consideration of both confidence level and reliability for CFRP laminates by combining fracture fatigue entropy (FFE) theory and knowledge of statistics. After carrying out distribution analysis and statistical hypothesis testing, it is found that the FFEs obey well to log-normal distribution and the average values and deviations of logarithmic FFEs under different stress levels exhibit no obvious difference. The gamma-p-S-N curves are predicted by single side allowance factor analysis and the prediction is found to be more conservative and have a larger scatter comparing to experimental results.

Automated summary

This study proposes a new methodology to evaluate the fatigue life of CFRP laminates, considering both confidence level and reliability. It combines fracture fatigue entropy (FFE) theory and knowledge of statistics. The study finds that FFEs follow a log-normal distribution, and there is no significant difference in the average values and deviations of logarithmic FFEs under different stress levels. The predicted gamma-p-S-N curves are more conservative and have larger scatter compared to experimental results.