COMPUTER-SIMULATION AND RELIABILITY-ANALYSIS OF FATIGUE-CRACK PROPAGATION UNDER RANDOM LOADING

In order to study the behavior of fatigue crack propagation and fatigue reliability of a structural or mechanical component under random loading, a numerical simulation scheme and other analytical prediction models are proposed. The paper consists of: (1) digital generation of random loading from random process theory; (2) numerical simulation of fatigue crack growth based on a fracture mechanics concept; (3) a modified rain-flow cycle counting method for the identification of stress cycles and stress amplitudes; (4) Weibull probability density fit and other statistical analyses for the stress amplitudes as well as the crack growth curves; (5) probabilistic models for the prediction of fatigue crack growth, fatigue life and fatigue reliability. Some conclusions are drawn at the end of this paper which can be used as references in the design of a structural or mechanical component under random loading.