Laboratory is an important element in the identification of a soil and is the next step after macroscopic research and fieldtests. The quality of samples supplied to the laboratory is an important factor that has a significant impact on the quality of laboratory tests. In accordance with the applicable provisions of Eurocod 7, for most tests, Class 1 and Class 2 samples corresponding to sampling category A are required. These are samples taken without destroying the structure, and with the preserved moisture content and porosity.
For example, for samples with a grade lower than A (B and C) the grading of grains, the boundaries of Attenberg, the specific gravity, the content of organic matter, the moisture content, can be determined . For class A samples we can further specify the boundaries of layers and such soil parameters as density, density index, porosity, permeability, compressibility and compressive strength. Laboratory results are usually collected in a table and on the tabs representing the individual studies.