Sears at Seven Corner, located on Leesburg Pike in Falls Church, Virginia consists of a retail complex with an elevated parking structure. The elevated parking structure is a separate structure at the rear of the complex. It consists of two levels, one elevated level and one level at grade. The structure is constructed of a reinforced lightweight-concrete deck supported by steel beams and girders that tie-in to steel columns. The steel columns extend below-grade and are supported by individual concrete footers. The lower level parking surface consists of asphalt.
TCE was requested to review the ongoing deterioration observed at the base of the garage columns at grade. Corrosion-related deterioration was observed to be significant at many of the columns reviewed by TCE. Section loss due to corrosion of the steel columns exceeding 50% was noted at several locations. This section loss had resulted in buckling failure of the columns at these areas. These buckling failures resulted in partial deflection of the elevated structure and caused damage to other structural steel elements.
TCE developed a shoring plan to stabilize the garage structure and to prevent further settling of the elevated structure. After the structure was stabilized, a full investigation of all garage columns was performed to determine the extent of steel deterioration. TCE developed a repair plan to raise the structure up to its original elevation and to repair the deteriorated columns and the damaged beams.
The structure was raised back to its original elevation. Deteriorated sections of the columns were removed and replaced with new steel column sections and the damaged beams were strengthen to their original integrity. The below-grade portion of the column sections were coated with a waterproofing membrane to minimize potential for future corrosion of the columns.
