The upscale open-air shopping center, Fashion Island, is located in Newport Beach in Orange County, Calif. A new five-story parking structure was being constructed for the shopping area, but an emergency situation arose after the columns were poured.
Two of the columns were not well vibrated, resulting in large voids around the anchors of the post-tensioning cables. The size of the voids averaged around 24 x 24 x 48 inches. To make the repair, the contractor needed 5,000 psi concrete with aggregates. Each column contained 13 post-tensioned cables and each cable was stressed at 5,000 psi. The challenge was to successfully flow the mix around the cables and then consolidate the concrete.
To repair the columns, 50 bags of Rapid Set Concrete Mix were used. The contractor, Bomel Construction, used a ½-inch drill drive with a paddle mixer in a 5-gallon bucket using 5 quarts of water. To make the mix more flowable, some Rapid Set FLOW Control was added to the mix. Then to cure, the top of the pour was kept wet with water for two hours.
The Rapid Set concrete reached 5,000 psi within 28 days as required. The entire repair was completed within two days.