Studying the Connection Between Fatigue Life and Modal Characteristic in Composite Structures Having Geometrical Singularities

Abstract

The relationship between fatigue life and modal parameters, such as natural frequencies, in fiber-reinforced polymer (FRP) composite structures was investigated. A progressive model of fatigue life prediction was utilized to estimate the fatigue life of a composite column subjected to cyclic loading, with modal analysis serving as the primary evaluation method. The methodology involves tracking natural frequency changes to correlate stiffness degradation with fatigue life. Validation of the model was conducted using previously studied composite components with varying geometric configurations. The results demonstrate a proportional decrease in natural frequencies with stiffness degradation, providing a reliable basis for estimating the fatigue life of composite structures.