The CBD Garage is a six-level municipal parking garage constructed circa 1980. The lower parking levels of the post-tensioned concrete structure had several locations with cracked and deflected concrete slabs. Since 2013, SGH has helped the City of Malden by assessing the structure’s condition and overseeing repair designs and administration.
Our condition assessments included visually surveying the parking structure and sounding representative areas to document the extent and location of any damage or deterioration. SGH also investigated the post-tensioned reinforcement throughout the garage, using ground penetrating radar and making observations at exploratory openings to evaluate the tendon’s condition of the tendons. Based on our observations, we developed remedial options, prepared cost estimates, and prioritized the repairs to help the city plan for the work.
SGH developed a rehabilitation program to extend the parking structure’s useful life. We collaborated with the contractor to develop a phased approach that allowed the garage to remain operational during the repair work. Highlights of our design include:
- Repairing broken and corroded post-tensioned slab reinforcement, considering the effects of detensioning and retensioning on the structure
- Performing localized concrete repairs at the parking decks and exit helix ramp
- Installing new waterproofing systems in areas with significant deterioration at the lower parking levels and a new epoxy overlay system at the exit helix ramp