Determination of resistance of aggregates to fragmentation by the impact test method
The main components of the impact tester:
- Lifting device, consisting of drop hammer, guides, lifting and drive motor, counters.
- Sample holder consisting of pestle and mortar with automatic contact pressure and adjustment device.
- Anvil.
- Base plate and dampers.
- Machine casing.
Test procedure:
Test procedure is defined in European Standard EN 1097-2 (implemented by ČSN EN 1097-2) Test for mechanical and physical properties of aggregates – Part 2: Methods for determination of resistance to fragmentation. Clause 6 – Determination of resistance to fragmentation by the impact test method.
For the purposes of assessing the performance of aggregates for railway ballast according to ČSN EN 13450, the test procedure, the same in principle but modified, is used according to the Annex D of this standard.
Test result:
The impact value SZ gives a measure of the resistance of aggregates to dynamic crushing. It is given as a percentage. Conditions for the course of the test and determination of the impact value are defined in the above mentioned standards.