Helical piles were determined to be the effective and practical solution for the project. The engineer design for the spa included four (4) “Chance” 2.875-.203 inch helicals. The round shaft helical piles with 8”-10”-12” triple-helix lead sections were utilized. The piles would support design working loads ranging from 15 kips. With the presence of the fill and weak native soils near the original ground surface, a minimum helical pile depth of 17 feet was secured.
A Toro-1000N compact skid loader was fitted with a custom mounting bracket to support the drive head with a rated output torque of 7,000 ft-lb. Additional extensions were required to reach the specified load capacity and structurally-tolerable parameters. The piles were advanced to depths ranging from 17 to 21 feet to achieve torque-correlated ultimate capacities of at least twice the design working loads.
The helical piles were installed by Coastal Foundation Solutions, a Certified Installer of Seawall Savers and Chance Helical Foundations Systems.