TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Method: The coating of the concrete surface with the top coat is carried out on dry stopper coat or on the stopper coat in wet-on-wet method, where the concrete surface is coated with only one top coat. The top coat is applied by rolling, high pressure spraying, air-mix- or airless spraying.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The polyisocyanate comprises aromatic, cycloaliphatic or aliphatic polyisocyanates. The aliphatic polyisocyanate comprises hexamethylene diisocyanate and/or isophorone diisocyanate. The cycloaliphatic polyisocyanate comprises 1,4-cyclohexyl diisocyanate. The polyaspartic acid ester comprises N,N'-(2-methyl-1,5-pentanediyl)-bis-1,1'4,4'-tetraethyl ester, N,N'-(methylene-di-4,1-cyclohexanediyl)-bis-1,1'4,4'-tetraethyl ester and/or N,N'-(methylenebis(2-methyl-4,1-cyclohexanediyl))-bis-1,1'4,4'-tetraethyl ester.    TECHNOLOGY FOCUS - POLYMERS - Preferred Components: The polyurea comprises polyaspartic acid ester. The coating materials are optionally formulated with reactive diluents. The coating material used in the stopper coat, is made of a solvent-free two-component polyaspartic acid ester. The solvent-free two-component polyaspartic acid ester coating material comprises a solvent-free and liquid polyaspartic acid ester and a polyisocyanate, which are present in a weight mixing ratio of 0.5:1-10:1. The low-solvent two-component polyurea coating material is a low-solvent two-component polyaspartic acid ester coating material made of a solvent-free and liquid polyaspartic acid ester and an aliphatic and/or cycloaliphatic polyisocyanate, which are present in a weight mixing ratio of 0.5:1-15:1. The solvent-free two-component polyaspartic acid ester coating material exhibits a pigment-volume concentration of 25-45%. The two-component polyurea used in the stopper coat, exhibits an intrinsic viscosity of 200-2000 dPas at 23 degrees C in a mixture. The low-solvent two-component polyaspartic acid ester coating material exhibits a solvent content of 4-20 wt.%, a matting in a gloss region at an angle of 60 degrees , of 10-35%, and a pseudoplastic flow behavior of 20-500 dPas. The top coat exhibits a layer thickness of 80-500 mu m. The coating system exhibits waterproof property after drying for up to 2 hours at 20 degrees C. EXAMPLE - No suitable example given.