Mechanism of rock failure due to static or dynamic loads is of immense importance to mining, civil and geo-technical engineers for ensuring stability of structures made in rock mass. Generally, this phenomenon is investigated using conventional methods like seismic, micro-seismic, acoustic, electromagnetic and other techniques. However, these methods do not provide comprehensive knowledge about failure process since data are collected at a few points attached to a rock sample. Often it is not possible to monitor rock deformation with time at every location in a structure and hence vital information regarding the failure process cannot be recorded for further investigation. On the other hand, these conventional sensors are prone to acquire noise from several machineries inside a mine, tunnel or cavern.
Advancement of Digital Image Correlation (DIC) technique exhibits the possibility for monitoring rock deformation or failure mechanism in test rock samples. In DIC, two images taken within a small time interval of a same object are compared to extract changes or movement of pixels while the object has undergone through a loading process. In this research work, rock surface displacement/deformation under uniaxial cyclic loading conditions has been analyzed using multilevel FEM-DIC techniques. This method is non-contact type and hence deformation can be estimated remotely for the entire face of the sample under investigation with continuous passage of time. The study shows that it is possible to identify deformation status on each and every point on the rock sample and results are comparable with the physical measurements.
