A Hybrid Numerical-Experimental Method for Caustic Measurements of the -lntegral
SourceThis paper presents a methodology of direct experimental measurement of the T*-integral, which has great potential as a nonlinear (elastoplastic) fracture mechanics parameter. A hybrid numerical-experimental method was developed to measure the T*-integral by the size of reflected caustic pattern. To this end, the formation process of the caustic pattern for an elastoplastic crack tip in a compact tension specimen was simulated by a previously developed finite element simulation technique aided by computerized symbolic manipulation. Experimental measurement of the caustic pattern in the compact tension specimen was also carried out. Both simulated and actual caustic patterns agreed very well. The relations between the T*-integral and the size of caustic pattern were obtained for various optical setup.