900 Parkaire Crossing Apartments

Situation

Cantsink was brought in by Ray Engineering at the request of the apartment management group to stabilize the foundation of an apartment building near Johnson Ferry and Lower Roswell roads. A resident in one of its upper units had repeatedly contacted management about cracks in drywall that were not permanently corrected with drywall replacement.

The resident, who has lived in that unit for 27 years, was happy with the overall conditions and management of the complex, but hoped for a solution to the drywall problems. Inspection revealed that one side of the foundation was sinking and needed underpinning to restore its structural integrity.

The likely cause was inadequate fill dirt under the foundation, located near a retaining wall.

Scope of Work

Because it involved a multifamily residence, the job presented a lot of special challenges with air conditioning units, gas meters and cable boxes located throughout the work site. This required special care.

First, the Cantsink crew had to determine precisely where all of the utility lines ran. It also meant that each hole for the underpinning installation had to be dug by hand to avoid damaging any pipes or cables on the property. In all, the job required 12 underpinning brackets.

As the digging began on the site, the crew also discovered an extra-wide footer 24 inches wide and 12 inches deep that was not attached to the building. The crew used a jack hammer to break through the footing in locations where the underpinning brackets were to be placed, then finished the preparation with a chipping gun to smooth the edges for bracket placement.

Anchor System

12 underpinning brackets were installed, comprising 21 feet of support below.

Results

The job required three days of work because of all the extra care and attention the crew had to use avoiding any possible damage to the building's systems. The work was completed while all these systems were protected and the sinking foundation is stabilized.

During installation, a Cantsink project supervisor met with the upstairs resident to advise him of the reason for the temporary disruption and noise of the installation work.

The resident expressed his relief that the source of the problem had been diagnosed and would be permanently corrected.