Fuzzy-random FOSM and its application in low cycle fatigue life reliability analysis of an aeronautical engine turbine disk

An approximate analytical method is presented to analyze reliability for the structure with fuzzy-random uncertainty in basic variables. On the basis of equivalent transformation from fuzzy possibility distribution (FPD) to random probability distribution (RPD), this contribution expands first order and second moment method (FOSM) for random reliability to that for fuzzy-random reliability. The expanded FOSM is illustrated by the way of the fuzzy-random low fatigue life reliability analysis about an aeronautical engine disk affected by fuzzy-random uncertainty. Comparison between the FOSM and the numerical simulation for the fuzzy-random reliability demonstrates the precision of the presented computational model.