FedEx Secondary 25

Geopier^® designed and installed Rammed Aggregate Pier^® ground improvement for support of forty (40) wind turbines at the Delta Wind project in Tunica, MS. The overall design accounted for several challenging site conditions including: 1. Soft/loose subsurface conditions, 2. High groundwater levels, 3. Normal and extreme loading conditions, and 4. Seismic loading and liquefaction associated with the nearby New Madrid fault (Mw = 7.5 and PGA up to 0.44g). The design was vetted by several internal and external reviewers to verify the stringent design criteria for the project were met.

Geopier utilized its X1® Drilled Rammed Aggregate Pier® System using cement treated aggregate (CTA) for construction. The use of CTA allowed for a design bearing pressure of 9,000 psf. The use of this nontraditional aggregate for pier construction was essential to providing a ground improvement system to meet the design needs for foundation support. Overall, the X1 solution helped FedEx save $1 million compared to the original auger cast piles. Finally, the Geopier solution included the special coordination of equipment and aggregate deliveries so that shipping and normal business operations were not disrupted.