A simple log normal random process approach of the fatigue crack growth considering the distribution of initial crack size and loading condition

The prediction of stochastic crack growth accumulation is important for the reliability analysis of structures as well as the scheduling of inspection and repair or replacement maintenance. Considering the log normal random process approach and a second-order approximation, a new simple stochastic crack growth analysis method is presented for practical applications. In addition to taking into account the correlation parameter, the loading condition and the initial flaw size distribution are accounted. Hence, it is flexible enough to cover a wide range of dispersion of the crack growth accumulation. The analysis method can be implemented easily using deterministic crack growth analysis results and estimates of the statistics of the crack growth behavior.