An Assessment of Factors Influencing Data Obtained by the Photoelastic Stress Freezing Technique for Stress Fields near Crack Tips

摘要

Factors which influence crack tip stress field data are identified as: (1) Non-linear zone near crack tip due to crack blunting. (2) Normal stress parallel to crack surface. (3) Location of region for data retrieval. The Kolosoff-Inglis solution is used in order to assess effects of crack tip blunting. A set of stress freezing photoelastic experiments are conducted on plates containing through cracks and results are compared with the Westergaard solution in order to assess the effect of Item 2 using appropriate Item 3 locations. A data conditioning computer program is employed to yield accurate values of the stress intensity factor from photoelastic data. (Author)