Unionport Bridge

SGH evaluated the concrete and developed recommendations to enhance the expected durability of the concrete. Highlights of our work include:

• Reviewing the New York City Department of Transportation specifications for high‑performance concrete, which was required for the new deck
• Using ground penetrating radar to identify locations where core sampling would not impact the embedded reinforcing steel
• Measuring surface crack widths and depths at extracted core samples
• Performing testing in our laboratory to evaluate the concrete’s chloride ion permeability per ASTM C1202
• Recommending the contractor apply a methyl methacrylate sealer to the approach span to reduce permeability
• Collaborating with the construction team to coordinate the bridge deck tining with the sealer installation