원공조치를 가진 탄소섬유강화 플라스틱 적층판의 피로수명에측

Fatigue Life Prediction of Circular Notched CFRP Laminates

Fatigue life prediction and fatigue behavior of circular notched carbon fiber reinforced plastic laminates are presented. Point and average stress criteria by Whitney and Nuismer are generalized to fatigue fracture criteria for notched laminates. Residual strength degradation model and the assumptions on the stress redistribution are introduced during the derivation of prediction equations. S-N curve, Basquin's relation, and H and H's FLPE1 are chosen for evaluation of residual strength of unnotched laminates and six prediction equations are derived. Experiments are performed using Graphite/Epoxy laminates whose fiber orientation is $[0$^\circ$/+45$^\circ$/-45$^\circ$/90$^\circ$]s. Presented prediction equations are reasonably close to experimental data and proposed appoach is found to be suitable to predict fatigue life of notched composite laminates.