Boston, MA
Massachusetts Department of Transportation, Callahan Tunnel Vent Buildings
Scope/Solutions
The Massachusetts Department of Transportation (MassDOT) owns several buildings housing large air exchangers to ventilate the Callahan Tunnel that connects East Boston and downtown. On the East Boston side of the tunnel, the buildings’ walls exhibited ongoing deterioration, including visible out-of-plane bowing, detachment of the brick masonry from the cinder-block backup wall, and partial collapse. SGH served as the structural engineer of record for the assessment and restoration project to address the distressed masonry walls.
SGH evaluated the 1950s vent buildings to understand existing conditions and evaluate options for repairs. Highlights of our work include:
- Using findings from our hands-on survey with laser scanning performed by another firm to develop topography plots showing the magnitude of outward bowing
- Assessing the stability of the buildings’ composite masonry walls
- Developing construction documents to restore and replace portions of the brick and masonry facade elements, while maintaining the buildings’ aesthitics and character
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Project Summary
Solutions
Repair & Rehabilitation
Services
Structures | Building Enclosures
Markets
Infrastructure & Transportation
Key team members
Greggrey Cohen
Managing Principal, Structural Repair and Rehabilitation, Boston
Additional Projects
Northeast
Massachusetts Water Resource Authority, Beacon Street Line
Constructed in the 1870s, the Beacon Street Line carries water under the MBTA Green Line tracks in the busy Brookline neighborhood. SGH evaluated the pipe to determine if workers could safely enter, designed the repair, and provided engineering support during construction.
Northeast
John W. Weeks Footbridge
As part of an on-call term contract with the Department of Conservation and Recreation (DCR) and with additional design funding provided by Harvard University, SGH worked on a two-phase project to repair and upgrade the bridge.



