Identification of isochromatic fringes - Simple guidelines are presented to number isochromatic fringes in static- and dynamic-photoelastic problems

In simple cases of static-photoelastic analysis, the numbering of the isochromatic fringes does not present unusual difficulties. In more complex cases, in particular wave propagation, the problem may be so difficult that few investigators attempt the analysis. In this paper guidelines to number the isochromatic fringes are presented. Advantage is taken of some topological properties as well as of the time and space derivatives of these isochromatic fringes. Several examples are discussed to illustrate the use of the guidelines. It is observed that under most conditions the guidelines are sufficient to number the whole field of isochromatics on photographs taken with the commonly used monochromatic light. © 1983 Society for Experimental Mechanics, Inc

Dynamic photoelastic investigation of interaction of stress waves with running cracks - A photoelastic study of interaction of stress waves with running cracks is conducted to investigate the influence of crack-wave interaction on crack-propagation behavior and crack branching

Dynamic photoelasticity in conjunction with high-speed photography was utilized in experiments to study the interaction of stress waves with a running crack. Experimental data were analyzed to study the effect of wave scattering about a moving crack tip. The results indicated a strong influence of stress waves on crack-propagation behavior and crack branching. © 1981 Society for Experimental Mechanics, Inc