Indirect tensile test modelling for inhomogeneous rock samples using digital image processing

The behavior of rock under different loading conditions is very important for the stability analysis and safety measures taken in mining engineering. Rocks are generally inhomogeneous in nature and contain different minerals, cracks, and pores. This inhomogeneity in rock causes departure in their behavior from known theories of rock failure based on homogeneous assumption of rock. In the research presented in this paper, inhomogeneity present due to different mineral constituents is taken into account for their mechanical strength analysis. Digital image processing techniques are utilized to capture this inhomogeneous nature. Region segmentation method and edge detection method are two popular image processing techniques used for this purpose. The obtained image data is then vectorized and transformed so as to feed it into numerical and structural analysis software. Brazilian indirect test is used for stress analysis of rock specimen. The results obtained from numerical modelling software and from laboratory tests show that the weakest mineral present in rock specimen generally controls the overall failure phenomenon for Brazilian tensile test.