Abstract:
In order to study the crack modes of Beishan granite under the indentation of a single disc rolling cutter, a series of linear cutting experiments are conducted on the Mechanical Rock Fragmentation Experimental Platform developed by Beijing University of Technology. During the experiment, a constant cross-section disc cutter with a diameter of 17 inches (432 mm) is used and a block of Beishan granite with the size of 1000×1000×600 mm is adopted. After the tests, it is found that there is a cracked part beneath the groove with varied fragmentation degree. Based on the observed crack mode and crack density, the rock sample is classified into re-compacted zone, crushed and cracked zone and intact rock zone, then the sizes and areas of these zones are summarized accordingly. Meanwhile the ultrasonic velocity tests and rebound tests are conducted to obtain the properties of different zones. Finally, it is found that these test results agree well with the fragmentation degrees of different zones. In addition, as the time of cutting increases, the areas of these zones expand significantly, while the properties of the corresponding zones almost keep constant.