Experimental and Numerical Determination of Strain and Displacement Fields on Brazilian Disk

The Brazilian test is a straightforward method of indirect testing that consists of applying a diametrically opposite load to a circular disk to determine the tensile strength of brittle materials, namely rock, concrete, and rock-like material. The indirect tensile strength is commonly determined by assuming that failure takes place at the location of the highest tensile stress, specifically at the center of the disk. However, prior studies have indicated that failure can happen outside the central region of the test disk when subjected to small angles of loading contact area for materials with low compression-tension ratios. So, to evaluate and visualize what happens during the test on the disk, we carried out an optical experimental test called Moiré interferometry, which can allow a field measurement of displacement and strain. To complete the study was implemented numerical simulations with the same conditions of the experimental work. It is safe to say that the interferometric Moiré technique works well for measuring the displacement field in this kind of test. This is held by the numerical simulation results.