Estimating Abrasivity of Rock by Laboratory and In Situ Tests

The degree to which a rock abrades another rock is called its “abrasivity”. Laboratory tests of abrasivity can be broadly divided into four kinds: drilling, rubbing, turning-operation and tumbling tests. The present study was initiated 30 years ago with the objective of investigating and developing methods for measuring rock abrasivity, and making some contribution towards understanding the relationships between the above test methods. Within the range of tests conducted, the turning-operation test turned out to be superior to the drilling test, albeit slightly, in terms of practicality. We have also conducted in situ tests using rock drills for the last 20 years. The results of those tests have been investigated and compared with the results of laboratory tests. There is a large degree of scatter in the data on gauge loss in button bits, which has obscured any correlations with laboratory data. Some correlations were found between height loss in button bits and laboratory findings.