Fatigue Scatter Factor Analysis of Airplane Structures Based on Zero-failure Data

In the fatigue life test of high-reliability airplane structures, a large number of zero-failure data can be obtained, in which case the fatigue life scatter factor is significantly different from that of complete data. This paper conducted a study to define a scatter factor correction coefficient for normal distribution and two-parameter Weibull distribution under the condition of zero-failure data and derived the difference of the scatter factor under these two cases theoretically. At the same time, in order to analyze the difference, a comparative analysis of numerical simulation results under a certain reliability index is presented. The results show that this method makes full use of the product information under the conditions of zero-failure data to enhance the structures' fatigue safe life and to meet the practical engineering requirements.