Experimental and Numerical Examination on Measurement of Stress Intensity Factors under Mode ‡T, ‡U and ‡V Loadings by the Method of Caustics
Masayuki SHOZU, Zheng LIN, Ryo IKEDA and Hajime HIROSE
Abstract:The experimental method of caustics is a useful technique for the determination of the stress intensity factor K. In this paper, the stress intensity factors under mode‡T, ‡U and ‡V loadings are measured by the method of caustics, and the effect of those loading modes on the measurement accuracy is experimentally and numerically examined. Furthermore, a numerical method based on the 3-D finite element method (3D-FEM), which can directly simulate the caustic images, is proposed. As a result, it is found that the minimum initial curve radius r0min obtained in this study depends on the type of loading that is of mode ‡Tor mode ‡U . In the case of mode ‡V loading, however, the measured value of K agrees with the theoretical one regardless of the change of the initial curve radius r0. And the simulated results are in good agreement with the experimental images. Key Words:The method of caustics, Mode‡T, ‡U and ‡V loadings, Stress intensity factor, Initial curve, 3-D stress field, Numerical method, 3-D Finite element method