Prediction of Delamination Growth Behavior in a Carbon Fiber Composite Laminate Subjected to Constant Amplitude Compression-Compression Fatigue Loads

J. Raju, D.S. Sreedhar, & C.M.

Abstract

A quasi-isotropic lay-up carbon fiber composite of 150mm x 150mm containing a central circular delamination of 30 mm diameter placed between 11th and 12th layer was modeled using 2D shell elements. Constant amplitude compression-compression fatigue load with Pmax= 87kN and stress ratio, R=10 was applied. The strain energy release rate (SERR) in front of the delamination contour was obtained using virtual crack closure technique (VCCT) from non-linear finite element analysis using ABAQUS code. The SERR were estimated from B-K law. Delamination extension due to the driving force GII was estimated from the mixed mode delamination growth law. The new delamination shape factor after application of a certain number of load cycles was determined. The results show that delamination grows subcritically under compressive loads to attain new shapes.