PHOTOELASTIC ANALYSIS OF ANISOTROPIC FIBER REINFORCED COMPOSITES

A theoretical and experimental investigation was made of the integrated photoelastic effect in a transparent fiber glass reinforced epoxy resin. Vacuum impregnation techniques were developed to render the material transparent. The integrated effect of the isochro matics and isoclinics in the material when subjected to both uniaxial and biaxial stresses was observed and compared to the predicted data. Isochromatic data proved to be representable by a proposed orthotropic stress-optic law. Isoclinics were predictable, but at a given point in a stressed model the isoclinic angle depends on both the fiber orienta tion with respect to the principal stress directions and the ratio of principal stress magnitudes. Thus, the isoclinics do not directly give the principal stress directions. At this point, the anisotropic photo elasticity solution has not been determined. © 1969, Sage Publications. All rights reserved.