Ductile Iron Piles
Ductile Iron Piles, like other deep foundation elements, allow structural loads to be transferred through unsuitable bearing strata (e.g., fill and organic soils) into more desirable geotechnical strata. These piles can be designed as friction OR end-bearing. Ductile Iron Piles can be considered as an alternative to drilled micropiles, helical piles, driven piles, augercast piles, and drilled shafts. Typical allowable design loads range from 25 to 100 tons. While these elements are largely utilized in compression, they can also be used in a tension application, or a combination of both.
Like other deep foundation elements, Ductile Iron Piles can be utilized in situations where conventional spread footing and/or driven pile foundation systems are either impractical or infeasible. Ductile Iron Piles distinct advantage is demonstrated by the speed at which they can be installed. Typical production rates range from 500 to 1,200+ ft/day. Ductile Iron Piles utilize a plug & drive connection with a belled socket on one end and a tapered spigot on the other. This allows for rapid pile connections (no welding) as piles are driven into the ground. Equipment required for installation of Ductile Iron Piles is a medium sized excavator and a percussion hammer (hoe-ram) with drive pin. When installing grouted friction piles, an oversized conical drive shoe is used. A grout box is added to the driving shoe, and grout is pumped through the pipe and exits around the outside of the pipe as it is driven forming a grouted friction pile. End bearing piles utilize a driving shoe and are hammered into bedrock until project driving criteria is met. Since Ductile Iron Piles do not generate spoils, they are well suited for where contaminated layers overlay bearing strata or where spoils cannot be conveyed off site.
Like other pile supported foundation projects, static load testing is performed on Ductile Iron Piles prior to the start of production to verify design. Phoenix performs load testing in-house, including submittals and reports. Phoenix has performed many Ductile Iron Pile projects and can provide a recommendation for when to use one deep foundation pile type over another.
Please see additional Ductile Iron Pile resources at: duroterra.com.
Typical Applications for Ductile Iron Piles