Characterization of damage initiation in fiber reinforced composites from high resolution experimental data

Experimental results, obtained from digital volume correlation (DVC) analysis are reported for the damage initiation of a single-edge notched cross-ply [90/0/90] laminate loaded in tension. The DVC data was obtained from images that did not require the addition of a foreign agent to create an internal speckle pattern. From the DVC results, it was observed that the damage initiation mode was delamination of one of the interfaces at approximately 24% of the ultimate load in a small region near the tip of the notch. This delamination of the first interface led to a stress redistribution that quickly caused other damage modes, thereby establishing the sequence of the progressive failure that occurred. These results are useful for establishing and validating progressive failure analysis models for fiber reinforced composite laminates.