Methods of Caustics is a powerful yet simple experimental technique useful for application to fracture mechanics problems where steep stress gradient leading to singularity of stress intensification are present. An experimental set-up was designed and investigation carried out to study the caustics resulting from mode-II fracture crack tip stress distribution. The details of experimental set-up and geometry of compact shear specimen used for the experimental investigations are described. The mathematical derivation and interpretation of caustics for evaluation of mode-II stress intensity factor are discussed. Accurate determination of optical constant of the material has been achieved by calibrating the specimen of same material and under same set-up. This has improved the accuracy in evaluation of the stress intensity factors. The experimental results are seen to compare very well with previously published analytical and experimental results.
展开▼
