Synthesized Analysis Method of Structural Durability and Damage Tolerance Based on Reliability

Based on the theory of reliability and the aircraft structural durability and damage tolerance, the synthesized analysis method of the durability and damage tolerance is proposed by studying the total process of crack initiation and crack growth. In the paper, the non-probability initial crack size in the damage tolerance design handbook is regarded as the threshold size, and the probability of the crack size exceeding the threshold size can be given by detection statistics data, and the probability distribution of crack size corresponding to given exceedence probability can be deduced, and this probability distribution is regarded as the probability distribution of initial crack size at probability damage tolerance analysis. The explicit expression of structural safety margin is also derived at the damage tolerance analysis in order to avoid the calculation of multiple integrals, which improves the calculation efficiency and easily uses the traditional reliability analysis methods to solve reliability such as first order second moment method and Monte-Claro. The numerical examples and comparative analysis with existing methods show that the method is of reasonable and efficient.