Wheaton Dumont Coop Elevator

Construction consisted of eight grain storage bins that were part of a new grain storage handling facility just south of Britton, SD. Six of the bins have diameters of 105 feet, eave heights of 84 feet, and capacities of 684,000 bushels (each). The smaller two bins have diameters of 60 feet, eave heights of 84 feet, and capacities of 214,000 bushels (each).

Soil conditions consisted of a thin layer of topsoil at the surface underlain by firm to stiff lean clay with sand and sandy lean clay (alluvium) to about 12 feet overlying firm to stiff elastic silt to the maximum explored depth of 91 feet.

The Rammed Aggregate Pier® (RAP) system was selected and 30-inch diameter Geopier GP3® elements were installed with a shaft length of 16 feet to provide an allowable bearing capacity of 5,200 psf. The Geopier system was recommended by the geotechnical engineer to provide an increased soil bearing pressure to reduce the bin ring wall foundation sizes and to reduce the total and differential settlement to reasonable levels. Over 3,000 RAP elements were installed in 27 days. The Geopier solution was verified with a modulus test during production that confirmed the installed piers would perform as designed.