The application of birefringent coatings to plane stress problem associated with orthotropic material is treated.
Isochromatic disturbance in the vicinity of a laminate at free-edge, due to the mismatch of Poisson's ratio between coating material and laminated composites and interlaminar stress transfer between discrete layers of the laminate, are investigated through birefringent coating method.
Photoelastic fringe patterns were quite different for laminates with different fiber-orientations. Poisson's ratio mismatch between coatings and composite was a major source of isochromatic disturbance at the free edge.
In this study the effect of Poisson's ratio mismatch and interlaminar stress are compensated to eliminate the source of experimental error. Experimental results were then compared with classical laminate theory and finite-element numerical result for a laminates with a circular hole.
