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
1 of 4
Project Summary
2024
Completion Date
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
Structural Engineering Division Head, New York
Additional Projects
Northeast
Logan International Airport, West Parking, Controlled Demolition of Post-tensioned Concrete Garage and Slab
A portion of the West Parking Garage fifth floor was cast on a snowy day. When the forms were stripped, contractor observed cracks and ice-filled voids in the slab. The owner and contractor needed to know if the 20,000 sq ft deck could be repaired or should be replaced.
Northeast
Logan International Airport Terminal E
After the contractor placed the 4 in. thick overlay, they observed lifted slab edges, cracks, and hollow-sounding areas in some locations. The contractor retained SGH to investigate the problem and provide repair options.