Surface treatment applied to concrete elements is a viable strategy to provide efficient protection against intrusive media which helps to reduce future maintenance and repair costs. In many Canadian cities, including the City of Winnipeg (COW), bridges that were built years ago have bare concrete decks, showing signs of cracking and deterioration, which need to be coated, treated, or sealed to maintain their serviceability and achieve their design service life. Typically, bridge decks are affected by freezing–thawing cycles, de-icing salts, and abrasion. The COW has considered different deck protection strategies including the applications of silane coatings, methyl methacrylate (MMA) healer-sealers, polymer-wearing surfaces, concrete overlays, and waterproofing membranes with asphalt overlays. It has been found that these coatings tend to detach/crack or require reapplications during their service life. Additionally, cracks were found to be a prime source of fluid ingression to initiate chloride induced corrosion of the bridge deck’s reinforcing steel. The authors previously completed laboratory studies to evaluate the efficacy of plain and nano-modified coatings as superficial treatments for concrete. In Phase I of this study, crackedcores were obtained from three bridges in Winnipeg, which were treated with various coatings in the laboratory to observe their resistance to the absorption of fluids. To verify the results in the field (Phase II), the same coatings were applied on a COW bridge deck, which is approximately 32 years old, to investigate the transport properties and microstructural changes after the coatings’ application. The current paper reports on the performance of silane, MMA, and colloidal nano-silica (50% nano-silica) coatings. Cracked and uncracked cores were extracted from each coating, and the barrier properties were implicated by absorption and penetrability to project their effectiveness.
