Why Driven Piles?
Driven piles have been used for hundreds of years as deep foundations. They rely on skin friction and end bearing to provide extremely high axial and lateral load resistance.
Driven piles can be used as foundations for any new structure. They are best applied in open areas away from existing structures to avoid accidental damage from the vibrations created from the driving hammer. Driven piling are the preferred deep foundation for most transportation facilities, including bridges, treatment plants, airport projects, and railroad work.
How it's done
Pile elements (wood, concrete, or steel) are impacted by a variety of pile hammers, and driven into the earth. A crawler crane carrying a large diesel powered hammer in between a set of steel leaders is the most common pile driving setup, but piles can be driven with vibratory hammers, gravity drop hammers, or hydraulic press hammers. Piles are loaded in between the leaders and simply driven into the ground to the desired depth or bearing capacity. The quality of a driven pile is certain. As a pile is driven, energy required to drive the pile is recorded and then converted into pile bearing capacity through a number of methods. Hence, "a driven pile is a tested pile." It is due to the reliability and history of driven piles that transportation departments demand the use of driven piles.
Driven piles are extremely strong and reliable. They are typically less expensive than drilled shafts but pricier than auger-cast piles. A major driven steel pile benefit is that if a pile does not provide enough resistance while driving, it can be spliced onto and driven deeper until it reaches a hard enough layer to achieve the required bearing.
Chris-Hill has driven piling since 1965 and has experience in driving wood, concrete, and steel piling in all types of soils and with a variety of hammers.