The office building and parking structure located at 400 P Street in Sacramento, California was looking for a solution to provide a stable platform to hold a large water tank. The area was located in a hard to reach, sandy hillside area outside the parking structure. The only access for our equipment was through the parking structure which provided height limitations.
The sandy hillside under the driveway accessing the parking structure was also deteriorating and washing away in the same area.
Helical piers were selected to provide the stability needed in the sandy area. The design called for four 288 helical piers with 8” – 10” and 12” triple-helix bearing plates. The piers, drilling down to 75’ to bedrock, were placed in a square which then allowed for the building contractor to install concrete slabs on top of each pier to support the weight of the water tank.
To solve the issue of the eroding soil under the driveway section, PolyLEVEL was injected to fill the void and provide the support needed with the addition of a retaining wall.
Installing Contractor: Foundation Repair of CA
Project Engineer: SFA Design Group, LLC
Products Installed: (4) Foundation Supportworks™ Model 288 Helical Piers, 8" - 10" - 12" Lead Section, installed to depths down to 75 feet, 25 kip design load