THE EFFECTIVENESS OF SPRAY-ON APPLICATION OF A HYDROPHOBIC ADDITIVE IN REDUCING CORROSION IN REINFORCED CONCRETE SLABS

Army facilities are made of common construction materials such as concrete and masonry.  These materials are highly porous and therefore susceptible to the intrusion of moisture and associated waterborne particles which can cause corrosion of the reinforcement resulting in reduction of the strength capacity of the structure.  Reinforcement corrosion affects all military construction and existing buildings where water migration through the concrete impacts the life and durability of the constructed facility, especially those near coastal zones.

The use of an integral hydrophobic material can eliminate the expensive costs of maintenance and repair associated with corrosion of reinforcement and can in turn extend the service life of the structure.  It can effectively block transmission of moisture through concrete and masonry structures, and will protect these structures from deterioration due to water penetration. 

The objective of this study is to determine the effectiveness of a hydrophobic additive, used for a spray-on application, in limiting corrosion when applied directly to the reinforcement after exposure to a corrosive environment.  Reinforced concrete slab specimens were cast and “pre-cracked” to directly expose the rebar to the corrosive environment.  Corrosion was quantified using Linear Polarization Resistance (LPR) Method.  This paper describes the testing that was performed and discusses the results for the hydrophobic product.