Bettendorf, IA - Sivyer Steel Company Chooses Helical Piles to Support their Equipment

Solution

Helical piles were selected over the drilled piers. Helical piles can be installed quickly using relatively small equipment within limited access and low headroom conditions. Helical pile installation does not require casing where high groundwater is present, and does not create spoils to be hauled off site. Each of the crane columns would be supported by a pile cap with three helical piles. Helical pile configurations consisted of both the Model 287 (2.875-inch OD by 0.203-inch wall) and the Model 288 (2.875-inch OD by 0.276-inch wall) hollow round shafts with 8”-10” double-helix lead sections to support design working loads of 13.5 and 27 kip s, respectively. The heavy equipment foundations consisted
of poured concrete mats supported by four to ten Model 288 helical piles (same plate configuration as described above) with various design working loads up to 27 kips. Standard extensions advanced the piles to depths from 14 to 20 feet below floor slab elevation to bear on or within the unde rlying bedrock. The piles were advanced to torque correlated ultimate capacities of at least twice the design working loads (FOS ≥ 2) or until spin-off on competent bedrock occurred. The piles were fitted with standard new construction brackets and cast into the poured concrete foundations. A total of 176 helical piles were installed at the site in 12 working days.