Boston, MA
Logan International Airport, I-90/Route 1A Interchange
Scope/Solutions
The modernization of Logan International Airport included the new I-90/Route 1A Interchange. SGH assisted several contractors that looked for assistance with understanding the complex system of reinforcement, post-tensioning ducts and anchorages, and conduits, as well as with concrete quality at a drilled shaft.
The elevated roadways are constructed of cast-in-place, post-tensioned concrete box girders and supported on individual concrete columns, concrete bents, and concrete abutments. The columns are supported on large diameter drilled shafts. SGH provided construction engineering services, including the following:
- Preparation of reinforcing bar shop drawings for box girders and straddle bents for direct use in fabrication, reducing delivery time by several weeks
- Preparation of integrated drawings of box girders and straddle bents showing post-tensioning ducts, anchorages and reinforcement, block outs, reinforcing steel, anchor bolts, earthquake restrainers, drainage systems, and utility conduits to help resolve conflicts between embedded items in advance of construction
- Evaluation of concrete quality in a major drilled shaft using extracted deep core samples
- Evaluation of out-of-tolerance drilled shaft reinforcement to show that the drilled shaft was able to carry design loads safely
- Evaluation and repair design for missing post-tensioning bars in one of the straddle bents
Project Summary
Solutions
New Construction
Services
Structures
Markets
Infrastructure & Transportation
Client(s)
Barletta Heavy Division
Specialized Capabilities
Temporary Construction
Key team members
Additional Projects
Northeast
Columbia Street Parking Garage
The owner of the Columbia Street Parking Garage needed a cost-effective design to replace the deteriorated precast concrete structure. SGH was the prime consultant, structural engineer, functional designer and precast concrete specialty engineer for the new structure.
Northeast
Government Center Station
Although the station was modified many times since opening in 1898, Government Center Station lacked accessibility. SGH designed temporary support of the existing structure during partial demolition and construction.

