Abstract: The failure process of granite plate with a hole at its center is examed under uniaxil compression using three-dimensional digital image correlation (3D-DIC) technique. The obtained evolutions of displacement field and strain field not only reflect the basic law of internal crack initiation and propagation but also reproduce the compression (parallel to the loading direction), stripping (vertical to the loading direction), expansion and spalling (vertical to the specimen surface) of the observation surface. The main findings are: 3D-DIC technique demonstrates its unique advantage in geotechnical experiments. The evolution of strain field during rock destruction is able to reflect the basic law of crack initiation and propagation which in turn can be observed by analyzing full strain contours. The evolution of crack is characterized with nonlinearity. The X-shaped local failure bands, forming slightly before rock destruction, eventually evolve into a macro-destruction zone, whose location is collectivelly controlled by the direction of load, the structure and interior heterogeneity of rock. It is effective to study the mechanism of rock deformation by using 3D-DIC technique, which can provide an important reference for the research on the macroscopic and mesoscpic.

Key words: three-dimensional digital image correlation (3D-DIC), rock plate with hole, non-contact, full-field strain measurement, crack propagation, failure