South Coast Helix Foundations, Inc.

Scope Of Work

Dixie Anchoring System Steel Piers were installed as mooring points (tie-downs) for the C-17 aircraft on three (3) concrete maintenance pads. Nine (9) mooring points were needed for each concrete pad. Twelve (12) inch diameter holes were cored through the eighteen (18) inch thick concrete pads. A Case 580 backhoe with a 10,000 ft-lb hydraulic drive head was used to install the twenty-seven (27) helix steel piers. Each helix steel pier was a 1 ¾" x 1 ¾" rounded corner solid square steel shaft with a double lead section consisting of an 8" and 10" inch diameter bearing plates. The helix steel piers were installed to depths between fifteen (15) and eighteen and a half (18 ½) feet with a measured torque of 10,000 ft-lb, in order, to resist the required 100 kips of uplift force. The final torque was verified by a shear pin indicator. The cored holes were filled with concrete and a chain shackle was bolted to the top of each helix steel pier. A tie-down chain can then be attached between the C-17 aircraft and the helix steel pier during high winds. The project was completed in three (3) days and was estimated to be at least two (2) to three (3) times more cost effective than alternative methods.