Abstract
Many U.S. Army facilities are made of common construction materials such as concrete masonry. These materials are highly porous, making them susceptible to moisture intrusion and associated waterborne particles. Such particles can cause corrosion of the reinforcement, and promote mold and mildew growth in confined spaces. Waterproofing solutions exist but are expensive, and most require maintenance over the life of the structure. This problem affects all military construction where water migration through masonry impacts the structure’s life and durability, especially facilities near coastal zones.
A hydrophobic admixture in concrete can prevent moisture migration and reduce the costs of maintenance and repairs associated with moisture-induced problems. The admixture reduces the water absorption properties of cementitious products such as block, mortar, and grout. As a result, the additive reduces the mold potential and protects concrete masonry walls from deterioration due to water penetration. This study evaluates the hydrophobic admixture by testing masonry walls, with and without the hydrophobic additive, exposed to a simulated wind-driven rain for a period of four hours. Results indicate that the hydrophobic additive does increase the time of wetness and decreases the amount of moisture that penetrates the wall.
