Abstract
In Western Europe the Cerchar scratch test is a very common testing procedure used for laboratory assessment of hardrock abrasivity. A wide variety of testing conditions and geological factors have been recognized to influence the test and the test result, the Cerchar Abrasiveness Index (CAI). The article presents some new findings based on a data set of 109 rock types. It emphasizes the use of the original steel quality for the testing needles and recommends five single test for every rock sample. A detailed evaluation of the needle wear flat should be made by microscopical analysis. For inhomogeneous rock types sample preparation with diamond rock saws is recommended to achieve even rock surfaces. These values can be compared with standard CAI values achieved on rough surfaces by use of a empirical equation.
| Translated title of the contribution | Testing conditions and geological factors influencing the Cerchar scratch test |
|---|---|
| Original language | German |
| Pages (from-to) | 110-113 |
| Number of pages | 4 |
| Journal | Geotechnik |
| Volume | 25 |
| Issue number | 2 |
| State | Published - 2002 |
| Externally published | Yes |