All photos courtesy Kryton International Inc. Feature A Modern Look at Improving Concrete Durability By Kevin Yuers, B.A. W hile many concrete structures have a design life of 50 to 100 years, not all live up to expectations. Much of the concrete infrastructure currently in service across North America is badly in need of repair or replacement, and this premature deterioration is a large hidden cost to owners. Concrete on its own is not waterproof. Normal concrete is filled with interconnected capillary pores allowing it to ‘breathe,’ but also permitting water to pass. Even high-performance concrete remains porous to a significant degree and may 32 March 2014 CC_March_14.indd 32 also be prone to cracking. Cracks are practically unavoidable in a concrete structure of any complexity. Once they form, they provide a direct path for water and contaminants to enter. Concrete structures also contain construction joints and penetrations for plumbing and electrical conduits. Cracks, joints, and penetrations are all areas where water can find its way into and through the concrete—especially when a head of water causes hydrostatic pressure to be exerted. As a result, if the structure is in a moist environment, especially close to saltwater, deterioration can occur much sooner than expected. Co nstruction Canada 2/11/2014 4:49 PM