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Geotechnical Engineering -
A Cost Effective Solution for Soft or Loose Soils: Expanded Polystyrene Geofoam

When working on roadway projects, do you occasionally run across situations where the underlying soft soil is too soft and compressible to carry designed loads, or the estimated time-rate of settlement of an embankment exceeds acceptable standards? Have costly corrective fill measures still resulted in significant settlement or decreased stability over time? Do you deal with failing slopes, excessive culvert loads, or problems with high lateral loads behind retaining structures? Expanded Polystyrene Geofoam (EPS Geofoam) could be your answer!

EPS Geofoam is a rigid foam plastic engineered with a unit density as low as 1 pound per square foot, thus delivering a material that is 100 times lighter than most soils. In particular situations this extreme difference in density makes EPS Geofoam an attractive fill option. A lightweight manufactured molded block, EPS Geofoam can be easily cut to any size or shape at the job site. Additionally, as an embankment soil alternative, EPS Geofoam can be covered to look like a normal slope embankment or finished to look like a wall. This technology, when properly applied in the appropriate situation is a field tested, budget-friendly winner. Here is a look at some of the less obvious but very important field proven benefits:

  • Accelerated construction
  • Payroll, transportation and equipment cost savings
  • Reduced labor time for construction
  • Exerts little or no lateral load on retaining structures
  • Easily constructed in limited right-of-way situations
  • Allows application in adverse weather conditions

Learn More About EPS Geofoam Technology

On Tuesday, June 22, 2004, the Rhode Island Department of Transportation (RIDOT) and the University of Rhode Island Transportation Center are joining together with the Federal Highway Administration's (FHWA) Rhode Island Division, the FHWA Resource Center, and the Rhode Island and Florida Local Technical Assistance Programs to present a one-day Demonstration Showcase on EPS Geofoam and recommended field applications - what to do and what not to do.

At the Showcase participants will experience and evaluate all aspects of this unique technology. Here's a look at what to expect:

  • Peter Osborn, FHWA Senior Geotechnical Engineer, will discuss the history and recommended applications for this technology.
  • RIDOT planners, designers and engineers will discuss every aspect of the showcased project.
  • Representatives from Cardi Corporation, the project construction contractor, will offer insights on the EPS Geofoam technology from their perspective as the installing contractor.
  • A guided field visit to a previous EPS Geofoam installation will provide an opportunity for in-use evaluation. There is not much to see...but that's the point!
  • A guided visit to the actual construction site where participants will gain a real-time experience with EPS Geofoam block preparation and placement.
  • A post-showcase support team will be available to assist with first-time applications back home.

Our goal is to provide a well-rounded professional learning experience including experienced professional support for your future EPS Geofoam implementation efforts. Decision-makers cannot afford to miss this opportunity. CEU and PDH credits are available for this Showcase.

Registration is $30 and includes all handout materials and lunch.

For those requiring overnight accommodations, a group room block has been arranged at the Radisson Airport Hotel in Warwick, RI, for $89 per night for single or double occupancy. You may contact the hotel direct at (800) 333.3333 or (401) 739.3000. Please mention "University of Rhode Island Transportation Center" to receive this rate. To register, or for more information on this Showcase, visit or call Cathy Manchester at the Rhode Island LTAP Center, 401.368.4850 or Chris Ritch, at the Florida LTAP Center, 352.392.2371 ext. 223. Showcase facility and overnight accommodation location maps will be provided upon registration.

Updated: 02/20/2015


United States Department of Transportation - Federal Highway Administration