Hydrophobic treatment of concrete as protection against chloride penetration

Hydrophobic treatment makes a concrete surface absorb less water and less chloride. Hydrophobic treatment was studied as a protection agninst chloride penetration from deicing salts. Test methods were designed. Nine hydrophobic products were tested, of which three complied to the requirements on finished concrete surfaces. The water absorption was strongly reduced and the penetration depth could be well over 2 mm. After 52 weekly salt pondinghlrying cycles the penetration of chloride was reduced by about 80% due to hydrophobic treatment. The water repellent effect remained constant over two years outdoors exposure. The influence of outdoor conditions and application variations on the performance was investigate