Newton, MA

1210-1230 Washington Street Garage


The 1210-30 Washington Street Garage is a three-level reinforced concrete parking structure with approximately 25,000 sq ft per level. The two-way slabs are supported by interior concrete columns with capitals and exterior concrete masonry bearing walls. The garage exhibited excessive deflections of the elevated decks at bay midspans, and extensive concrete cracking and concrete spalling. The owners retained SGH to perform a comprehensive survey and investigation involving structural analysis, load testing, remedial CFRP-strengthening design, and construction administration during repairs.

Highlights of SGH’s work for this project include the following:

  • Used ground penetrating radar (GPR) testing to determine the location of top and bottom reinforcement in the slabs
  • Performed a structural analysis of slabs based on as-built conditions to identify structural deficiencies
  • Determined that several negative-moment slab regions were deficient to support the code-prescribed design loads
  • Performed cyclic load testing to demonstrate that the as-built garage had sufficient strength (ACI-440 “threshold” strength) to qualify for strengthening with a carbon fiber-reinforced polymer (CFRP) system
  • Developed a rehabilitation program, including repair of deteriorated concrete, addition of deck waterproofing and drains, and strengthening of concrete slabs with near-surface-mounted (NSM) CFRP bars
  • Conducted construction monitoring during rehabilitation

Project Summary



Completion Date


Repair & Rehabilitation
Structures | Applied Science & Research
Hinckley, Allen & Snyder
Specialized Capabilities
Repair & Strengthening | Physical Testing

Key team members

Paul Kelley
Paul Kelley
Senior Principal
Gustavo Tumialan
Gustavo Tumialan
Associate Principal