Montgomery County Garage 49 Rehabilitation

The Garage 49 post-tensioning repair project involved the performance of major structural and waterproofing repairs to the five-level cast-in-place concrete post-tensioned structure. The combination of poor design and construction details resulted in severe cracking and deflection of the elevated decks of the parking structure.

The visible signs of distress led the owner, Montgomery County, to conduct a condition survey in 2004 that included physically exposing and examining a section of the post-tensioning system across a 60-ft wide section of the elevated deck from column-to-column, along a construction joint. Exploratory work revealed areas where over 40% of the uniform cables across the slab section had failed due to structural design deficiencies and corrosion-related deterioration.

The survey led to the installation of emergency shoring along construction joints throughout the garage until a thorough repair program could be performed. The scope of services included concrete repair and renovation, caulking and sealing, reinforcement repair, waterproofing and protection, capital planning and budgeting, project management, and structural evaluation and repair.