FATIGUE DAMAGE-STRENGTH RELATIONSHIPS IN COMPOSITE LAMINATES.

This report is Vol. I of a 2-part final report on a program the objective of which was to investigate the precise nature of the damage events caused by cyclic (fatigue) loading of composite laminates that are directly related to fracture of those laminates, to develop a conceptual understanding of how those damage events reduce the residual strength of the laminates, and to determine how the collective damage condition following long-term cyclic loading precipitates the final fracture event. A wide variety of destructive and nondestructive experimental evaluation schemes was used in the program, and several analytical efforts were conducted to support the experimental activities.