Improved hydrophobic property of pavement and bridge concrete with silane coating

Hydrophobic property of concrete with different mixture was studied before and after coating two types of silane products. Adsorption mass of water and NaCl solution of concrete surface were adopted to determine the hydrophobic property. The results show that the water adsorption ability of concrete without silane coating decreases with the higher strength and more air content of concrete. The NaCl solution adsorbed by concrete during 6 hours is 20 to 30% higher than the water. The coating of either cream or liquid phase of silane markedly improves the hydrophobic property of concrete surface and reduces the water adsorption mass of concrete during 6 hours by 90%. For concrete with a lower strength and less air content, the coating of silane shows a better improved hydrophobic property of concrete. The coating of either cream or liquid phase of silane reduces the NaCl solution adsorption a little more than the water adsorption for every concrete.