Parking Garage needs major repairing

Task: To perform the repairing of concrete, replace expansion joints, and install a urethane deck coating on the condominium's parking garage.

Structural Details: The garage was designed with an elevated flat slab with banded post tension cables running over the column lines in two directions.

Problem: Deterioration of the mono-strand post tension cables because of the lack of proper coverage over the cables had allowed water infiltration.

Initial Survey: An initial Survey of the post-tension cable system was conducted. The initial phase of the survey examined the condition of the high and low points of the topside and underside of the slab to determine positive and negative reinforcement. Technicians also looked to see if water had infiltrated the bottom of the sheathing. While on the surface it was apparent that only 2 cables were broken, careful investigation located 9 others that were broken or close to breaking. Ultimately, it was determined that 7 main cables needed to be repaired, 8 anchors had to be replaced, 5 add-ons were required, and 108 anchor pockets needed cleaning and trimming.

Out Approach: The repair suggested is to be consisted of greasing and re-sheathing of the unbroken exposed strands, full length cable repairs, replacement of extensively corroded anchors with excessive slippage and loss of section, and cleaning and trimming of anchor pockets. Additionally, it has been recommended that sacrificial anodes should be placed every 20 to 24 inches per square foot area and the reinforcing bars treated with a corrosion inhibitor (except in areas where leads from the anodes tied onto the bar). The skill of the crew is a deciding factor for success of repairing by keeping concrete removal to a minimum level and the prompt delivery of materials.