Compaction control on site, in the field or in the laboratory, determination of Proctor density or water content are just a few of the standard tests used to provide a solid and stable subsoil. 

Different types of soil can be found all over the world: stony subsoil (e.g. Keuper marl), sand, loamy soils, clay or man-made hydraulically bound base layers (rock compacted with cement). Depending on the composition, different properties arise, which must be examined before construction. 

Specifically determining soil strength, layer probing, water permeability and shear strength are important points that can mean real money for a construction project. If you know in advance what type of soil you will be dealing with, you can avoid unexpected additional investments.