EN 12326 - Water Absorption and Freeze-Thaw Resistance

Water Absorption

If the water absorption is less then ≤ 0,6 %, the freeze-thaw resistance of a slate is proven. If the water absorption is > 0,6 % the comformity has to be proven by carrying out the test for the freeze-thaw resistance.

Freeze-Thaw Resistance

During this test the change of the bending strength after the test of the freeze-thaw-resistance is determined on 20 pairs of samples. This 20 pairs are divided in two groups of 10 pairs: on one group the bending strength is determined without carrying out the freeze-thaw-cycle. On the other group, the bending strength is determined after carrying out 100 freeze-thaw-cycles. Afterwards, the bending strength and its possible changes are determined. In addition, the bending strength of both groups or pairs, respectively, has to be compared.

Principle of the Freeze-Thaw Resistance test
(Biegefestigkeit = bending strength, Vergleich = Comparison).

When applying the Student-t-method with a significance niveau of 2.5 %, the slate shouldn't show a significant change of the bending strength.
If the average bending strength after the freeze-thaw-cycles is the same as before or even exceeds it then the Student-t-method is not demanded.