The slab test is a test of the freeze–thaw scaling resistance of concrete both with water and with a sodium chloride solution. It can be used either to compare new constituents or new concrete compositions against a constituent or a concrete composition that is known to give adequate performance in the local environment or to assess the test results against some absolute numerical values based on local experiences.

Examples of slab-test standards:

• CEN TS 12390-9
• SIA 262/1 annex C
• XP P18-420

Slab specimens, sawn from concrete test specimens (Figure 1), are exposed to freeze–thaw cycles in presence of a 3 mm deep layer of de-ionized water or 3 % sodium chloride (NaCl) solution. The freeze–thaw resistance is evaluated by determining the mass scaled from the testing surface after 56 freeze–thaw cycles.

One of the difficulties of these tests is the sealing of the sample. The sodium chloride solution should not leak on the sample edges. The slab test frame guarantees an optimal sealing of the samples and defines precisely the surface area exposed to the saline solution, which increases the reproducibility of the test.

The frame is intended for single-use, i.e. the test specimen is usually disposed off including the frame after the test.