Exploration of a Visual Stress Measurement Instrument for Transparent Materials Based on Chromatic Polarization

Addressing the issues of low visualization and insufficient quantitative analysis in traditional stress meters, this paper designs a visual stress measurement device based on the photoelastic effect and digital image processing. This device visualizes the photoelastic effect of epoxy resin materials through a polarized light field and utilizes software to process the interference images, achieving visual reconstruction and quantitative analysis of stress distribution. Experiments were conducted to measure the stress distribution in an epoxy resin disc subjected to external pressure and a catenary arch bridge. For the disc, the experimental measured stress values showed a relative error of less than 5% compared to theoretical solutions. For the arch bridge, the experimental results indicated uniform stress distribution, verifying the theoretical characteristic that the pressure line along the axis direction of the catenary structure under uniform load. This device combines dynamic visualization of stress fields with static quantitative analysis, providing an intuitive and reliable tool for engineering stress analysis and experimental teaching. It is suitable for observing and studying stress transfer paths in complex structures in undergraduate physics experiments.