Out of plane displacement was measured by the shadow moire method combined with digital image processing for composite laminates subjected to compressive loading with through-the-width delamination.
In the experiments, experimental setup was constructed for accurate measurement of the parameters for shadow moire. For the processing of the moire fringe pattern, the image processing program was developed by the following algorithm. First, the moire fringe was sharpened using peak- detection method. Second, the order of fringe was given to the sharpened fringe, and the fringe which has the same order was recognized through grouping procedure. Then the out of plane displacement was obtained. The out of plane displacement of whole field of specimen was measured when buckling was occurred. The experimental results were compared with those of finite element analysis. In the finite element analysis, the eight-node degenerated shell element was used and the contact between laminates was considered using beam element. The results of experiment and finite element analysis show good agreement.
