The original design for this large new communication tower called for open-end driven steel piles. However, various site and soils conditions made it necessary to look at alternate methods to support the tower foundations.
Our engineers provided two options for a screw pile – one grouted and one ungrouted. The reason for these options were: 1. the project was time-sensitive and 2. there were more choices for selecting the most readily-available material to complete the project.
The pile chosen was a an 8 5/8″ pipe pile with triple 36” helices. Pile depth averaged 50 feet with install torque of up to 82,000 ft-lbs. A total of 15 piles were used in the design. Factored ULS loads per pile: 216 kips compression and 95 kips in tension. Soils variety of silts to depth.