United States Gypsum

October 6, 2022 Melanie Chaney


  • Owner // United States Gypsum
  • EOR // Edward Green USG, Southard OK
  • Average Test Load // 90,000 lb
  • Installation Torque // 7,000 ft-lbs
  • Average Pier Depth // 93′
  • Number of Placements // 396


This manufacturing plant is situated on a site with 20 to 25 feet of waste fill consisting of gypsum, chunks of concrete and reddish brown clay. Below this level was sand and clay fill, over silty clay with weathered rock fragments. At 34 to 39 feet a layer of weathered shale was encountered with Standard Penetration Blow Counts of 50/2”.


With over 37” of settlement the engineers recommended removing the failed and broken concrete floor, compaction of new fill and installing New Construction Helical Piers with 12 inch square Pier Caps at 10 feet on center. A new reinforced concrete slab cast in the area of the major slab failure. In other areas where slab was serviceable, the engineers recommended permanent stabilization and restoration using Helical Slab Channel Piers. The Slab Piers were installed through an 8 inch diameter hole, cored through the existing slab.


The slab piers are installed quickly through the slab using either machine mounted or hand-held vibration free hydraulic equipment.


In 1999 the project was completed ahead of schedule, thanks to the compact installation equipment the plant operations continued at 100%. In 2010, over ten years later there are no more problems.