Recently, a couple in Flowery Branch, GA reached out to us about their sunken driveway. They had been working from home, no thanks to the Coronavirus pandemic when they began to notice that their driveway was sinking. Their house is located on a hill and due to poor compaction during construction, the driveway gradually began to sink and slide down the hill. To make matters worse, their walkway was also sinking and had become a trip hazard.
The Ground Consolidation Services crew showed up for the appointment prepared and ready to observe all GCS COVID-19 Safety Guidelines. The driveway repair was the easiest part for us. We started by drilling small non-invasive 3/8” holes into the slab. Next, we injected Alchemy Spetec’s AP Lift 430 high strength polyurethane foam through the injection holes. The expanding structural foam travels the path of least resistance, therefore, filling all void areas as well as compacting any loose soil under the slab. Once the soil is compacted the expansion of the foam allows us to lift the slab as close to the original position as possible. In this case, we were able to raise the slab to within an eighth of an inch of its original position.
We inspected the walkway and observed that it had settled about 1.5” into the soil. That wasn’t all. The edge of the sunken part of the slab had also wedged under an adjacent level section. This damage was a result of poor drainage as well as compaction issues.
To repair the damage, we had to saw-cut at the point of the failed expansion joint located between the two concrete slab sections. This freed up the sunken slab for us to perform the lifting process. We carried out the same steps as the driveway repair by drilling 3/8” holes in the slab and injecting AP Lift 430 to level it with the other section.
The homeowners were thrilled with the outcome!