A commercial property management company noticed a separation between tilt wall panels, and the leave out tied into the panel was sloping toward the exterior wall in this area. After doing a comprehensive assessment, it was determined that a section of the tilt wall had sunk 2″. This part of Dallas doesn’t have any trace of bedrock for at least the first 50′ deep from grade level, and the builder piers are often only 20-25′ deep. It is not common in this area for the weight of these panels to cause the builder’s piers to sink further unless the piers are in rock.
Installed 82 steel piers under the affected area and disable 23 of the existing builder piers currently tied into the foundation to lift the structure back near its original position. Once the building has been lifted in place, we shim the gap we create between the builder piers and the foundation and shim our piers.
After breaking through the concrete to create temporary access to excavate below the foundation, we did our first test pier, and we went 52′ deep. The rest of the piers averaged about the same plus or minus a couple of feet, but this validated our suspicion based on our experience. Once all of the piers were driven and supporting the wall, we then disabled all of the builder piers to enable us to raise the building. The weight of the building required 20-ton hydraulic jacks to lift the building, and we were able to get all of the lift necessary. After shimming the piers with our 1/4″ steel spacers, we then tamped the dirt back in the holes, patched the concrete, and power washed the sidewalks and parking lot. The entire project took 11 days from start to finish.