Compressive Strength Test (Crushing Strength Test) of Stones
[IS:1121 (Part 1)]
- Take samples of stones weighing at least 25 kg each.
- Specimen species should be in the form of cubes or cylinders.
- The lateral dimension or diameter should be of 50 mm at least.
- The ratio of lateral dimension or ratio of height to diameter should be 1:1.
- A minimum of three specimens should be used for testing.
- Specimen is immersed in water at 20 to 30 °C for 72 hours. (Test in saturated condition)
- Specimen is dried in an oven at 105 ± 5 °C for 24 hours. (Test in dry condition)
- Then it is cooled in a desiccator to 20 to 30 °C.
- Later, it is tested in Universal Testing Machine.
- The load is gradually applied at a rate of 14 N /sq. mm /min (14 newtons per millimetre square per minute) until the specimen breaks down.
The Compressive Strength is then calculated by the formula:
*When the ratio of lateral dimension or ratio of height to diameter differs from unity by 25% or more then Compressive strength in Calculated by this formula: