An Approach to General 3-D Stress Analysis by Multidirectional Scattered Light Technique

Abstract

Scattered light photoelasticity provides a nondestructive analysis of stress components on a plane layer in the incident light path. For general three dimensional stress fields, however, the effect of birefringent axis rotation has to be taken into account, and hence the technique has been limited only in application to plane stress or symmetrical stress distributions.

In this study, the authors propose a method for determining not only the secondary principal stress difference, but also its direction, using multiple image data obtained by combination of the angles of incident polarization light and observation. As an example, a sphere under a pair of diametrical compressive forces is analysed to determine both the principal stress difference, and their directions in layers, with or without the rotation of the principal birefringent axis. The results show good agreement with theoretical analysis.