Study on Superhydrophobic Coatings for Concrete Surfaces

Concrete is one of the most versatile and important materials in civil engineering constructions. It is being used from ordinary platforms to many mega- structures. Durability of this important material is still a matter of great concern among civil engineers all over the world. Durability of concrete is affected mostly by intrusion of aggressive species from the immediate environment. Therefore it is an absolute necessary to block the pores, voids, capillaries, interconnecting pores and other surface defects of concrete surfaces. This can be achieved by proper coatings, particularly by superhydrophobic coatings (lotus leaf coating). In this study superhydrophobicity is achieved by using Silane, Siloxane, Silicone as binder with Nanosilica, Silica fume, Micro silica, TiO2, etc. Twenty eight different coatings were formulated and applied on concrete surfaces to study the hydrophobicity and superhydrophobicity. The best coatings were selected based on contact angles and roll on of water droplets and they never stick to the concrete surface. These coated surfaces are photo and video graphed and well established and discussed in detail.