Ground Improvement

Ductile Iron Pipe Piles (DIP’s)

Ductile Iron Piles (DIPs) are a pre-fabricated driven pile system utilizing high-strength ductile iron pipes that transfer the load from a footing or pile cap, or heavily-loaded slabs to a stiff soil or rock layer to control settlement of a structure.  DIPs can be designed for end-bearing or skin friction depending on the stratigraphy and loading conditions.

GeoStructures offers Ductile Iron Pipe piles on a design-build basis.  They can be used as the primary support for a structure or used in combination with a structure supported on conventional spread footings on natural soil or soil improved by Geopier or RIC Technology.

Quick Installation – Simple Connections using Bell and Spigot Connections

Why Ductile Iron Piles?

Ductile Iron Pipe Piles can be the most cost-effective option for foundation support of buildings when:

  • Access is limited
  • Vibrations are a concern
  • New footing construction abuts existing footings
  • New foundations abut existing or future utilities
Limited Access

Inside Buildings – DIP’s can be installed inside buildings that are accessible to full-size excavators. Custom DIP lengths can be used for areas where overhead clearance is limited.

Tight Job Sites – limited access+limited room for equipment+high capacity piles needed=DIP’s

Ductile Iron Piles being installed at The Adele, Washington, DC  
Width between buildings is approx. 46 feet. Note historic façade saved in the background.

Vibrations

The high-frequency tamper that is used to install Ductile Iron Piles generates minimal vibrations, well below the peak particle velocities acceptable for adjacent structures. The charts below document data from previous installations. Technical papers on the subject can be found in the Ductile Iron Pile Library section of the website.

Adjacent Buildings Or Utilities

DIP’s can provide a simple high capacity solution when projects require installation adjacent to existing structures or utilities, or when vibrations or excavation phasing create challenges for ground improvement techniques.

Center for Innovation and Technology Parking Deck, Raleigh, NC Parking Deck Foundations supported by Geopier elements and DIPs. DIPs used for footings adjacent to existing stormwater detentions structures

The Adele, Washington, DC – DIPs installed within 1 to 2 feet of existing foundations.

Alternate Driven Piles, Augercast Piles or Micropiles

Benefits of Ductile Iron Piles vs. other Pile Systems

  • Can be installed on Tight Sites with limited access
  • Low Mobilization Costs & Readily Available Materials
  • Variety of Low and High Capacity piles allows for use on many projects
  • Quick Installation – short sections – simple bell & spigot splice
  • End-bearing driving criteria confirms capacity
  • Can resist uplift and lateral loads

Variety of Sizes and Structural Capacities

A variety of capacities allows for use on both large and small projects.

3rd and New Street Building, Bethlehem, PA -Frictional DIP with outer and inner Grout column being installed.

3rd and New Street Building, Bethlehem, PA – Load Test Results for DIP with 80-kip design capacity controlled by skin friction.

Easy cutoffs – Easy to cut off piles to design length. Excess pipe reused as starter pile for next pile.

Ductile Iron Pile Case Studies and Videos

The following links provide brief case histories for projects that used Ductile Iron Piles:

Virginia Tech Brodie Hall, Blacksburg, VA
REI @ Pike and Rose, North Bethesda, MD
The Adele, Washington, DC
North Carolina State University – Center for Technology & Innovation Parking Garage, Raleigh, NC

A Video of a typical installation of DIP’s for a bridge project.

More Information on Ductile Iron Piles is available in the Library section of our website.