Bronx, NY
Unionport Bridge
Scope/Solutions
During construction of an approach span to a new bascule bridge, New York City Department of Transportation questioned the finishing procedures and long-term durability of the concrete bridge deck. Working for the construction team, SGH evaluated the concrete finish and materials to determine if the in-place materials satisfied the project specification requirements.
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
Project Summary
Solutions
Evaluation
Services
Structures | Applied Science & Research
Markets
Infrastructure & Transportation
Client(s)
Unionport Constructors, JV
Specialized Capabilities
Repair & Strengthening | Materials Science
Key team members
Nathaniel Smith
Managing Principal, Structural Engineering, New York
Additional Projects
Northeast
Massachusetts Water Resource Authority, Walnut Hill Treatment Plant, Cosgrove Intake Pipeline
SGH provided emergency response and evaluated the risk of failure resulting from the leak, inspected the pipeline to determine the cause of the leak, and developed a repair scheme.
Northeast
275 Wyman Street
SGH was the structural engineer for the five-story office building, plaza structure, and parking garage, and also consulted on the building enclosure and plaza waterproofing.



