Geofoam Research Center

Generic Specification for EPS Geofoam
  1. Scope
    1. This specification covers the types, physical properties and dimensions of rigid cellular polystyrene intended for use as geofoam.
    2. This specification does not cover the layout, placement and workmanship for proper installation and performance of expanded polystyrene geofoam.
    3. Rigid cellular polystyrene geofoam covered by this specification may need protection from certain chemicals, environmental exposure, and concentrated loads. Additional design considerations may include thermal conductivity and buoyancy. Guidelines regarding these end use considerations are included in Appendix X.1.
    4. This specification does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user to establish appropriate safety and health practices and to determine the applicability of regulatory limitations prior to use.

  2. Referenced Documents
    1. ASTM Standards
      C 203 Test Methods for Breaking Load and Flexural Properties of Block Type ThermalInsulation
      C 578 Standard Specification for Rigid Cellular Polystyrene Insulation
      C 390 Criteria for Sampling and Acceptance of Preformed Thermal Insulation Lots
      D 1621 Test Method for Compressive Properties of Rigid Cellular Plastics
      D 1622 Test Method for Apparent Density of Rigid Cellular Plastics
      D 2863 Test Method for Measuring the Minimum Oxygen Concentration to Support Candle-like
      Combustion of Plastics (Oxygen Index)

  3. Terminology

    3.1 Definitions:

    3.1.1 Terms used in this specification are defined in Terminology D XXX.

    3.1.2 Geofoam - block or planar rigid cellular foam polymeric material used in geotechnical engineering applications.

    3.2 Description of Terms Specific to this Standard

    3.2.1 EPS xx - letter designation for expanded polystyrene geofoam having a minimum density of XX kg/m3 (lb/ft3).

    3.2.2 RCPS - common letter designation for EPS rigid cellular polystyrene geofoam covered by this specification.

  4. Ordering Information

    4.1 Acquisition documents shall specify the following:

    4.1.1 Title, number and year of this specification.

    4.1.2 Type, or minimum density required, as per Table I.

    4.1.3 Total product volume required of each density, or Type.

  5. Materials and Manufacture

    5.1 EPS geofoam shall be formed by the expansion of polystyrene resin beads or granules in a closed mold. EPS geofoam may be manufactured with reprocessed polystyrene foam (regrind); however, the percentage of reprocessed polystyrene foam (regrind) shall be qualified by an accredited and independent third party.

    EPS geofoam shall be of uniform density and have essentially closed cells. EPS geofoam is an organic material and is considered combustible. It should not be exposed to flames or other ignition sources.

  6. Qualification Requirements

    6.1. The minimum physical properties listed in Table I constitute the product qualification requirements for commonly manufactured types of EPS geofoam.

    6.2 EPS Geofoam Types - EPS geofoam having properties greater (other) than those minimum values listed in Table I can be manufactured as specified. It is the user's responsibility to specify the required density and to obtain supporting documentation regarding physical properties from the material supplier.

    6.3 Combustibility Requirements - All EPS geofoam shall contain sufficient flame retardants to meet a minimum Oxygen Index of 24 per cent by volume as per ASTM D 2863 and Table I.

    6.4 Curing - Unless otherwise specified in the contract, EPS geofoam shall be cured for a minimum of 24 hours before delivery and inspection.

  7. Availability and Dimensional Tolerance

    7.1 Availability - The EPS geofoam materials covered by this specification are commonly available in the size range shown in Table II. Specific geofoam block dimensions vary by manufacturer equipment characteristics.

    7.2 Dimensional Tolerance - Unless otherwise specified, the acceptable length, width, thickness, flatness and squareness tolerance criteria on RCPS geofoam shall not exceed + 0.5 per cent.

  8. Damage and Degradation

    8.1 Damage - EPS geofoam as delivered to the project site shall have no defects that will adversely affect its service and work-ability qualities. Material units that manifest unacceptable surface or volumetric damage shall be replaced.

    8.1.1 Surface Damage - Damage to load bearing EPS geofoam surfaces shall be limited to less than 20 per cent of the equivalent load bearing area of the unit.

    8.1.2 Volume Damage - Volumetric damage of EPS geofoam shall be limited to less than 1 per cent of the volume of a single unit.

    8.2. UV (Ultra-Violet) Degradation - Discoloration and dusting of EPS geofoam caused by extended exposure to sunlight shall be removed by pressure washing of load bearing surfaces, unless otherwise specified.

  9. Inspection

    9.1 Sampling - unless otherwise specified in the purchase order or contract, the material shall be sampled for inspection in accordance with Criteria C 390.

    9.2 Weight - determine the weight of selected full size units in accordance with Test Method D 1622, or as specified.

    9.3 Dimensions - verify specified dimensions and tolerances, as prescribed in Test Method D 1622 and section 7.2 of this specification.

    9.4 Density - compute the density of test samples in accordance with Test Method D 1622.

  10. Acceptance or Rejection

    10.1 Material that fails to conform to this specification shall be rejected promptly in writing. The manufacturer or supplier shall have the right to re-inspect the rejected shipment and resubmit selected units for acceptance under tightened inspection.

  11. Certification

    11.1 Unless otherwise specified in the purchase order or contract, the manufacturer or supplier shall furnish a qualification certificate from an accredited and independent third party stating the manufacturer is capable of producing the EPS geofoam properties listed in Table I. A report of the certification test results shall be furnished to the end user upon request.

  12. Product Marking

    12.1 The following shall be marked on each whole unit of product:


    13. 12.1.1 Manufacturer's Identification,

    12.1.2 Date of Manufacture,

    12.1.3 Type, (See Table I),

    12.1.4 Weight or Density, and

    12.1.5 Resin Supplier.

  13. Key Words

    13.1 block; board; cellular polystyrene; EPS; expanded polystyrene; extruded polystyrene; foam plastic; geofoam; RCPS; reprocessed; rigid cellular polystyrene.

  14. Appendix (Non-Mandatory Information)

    X.1 End-use Considerations

    X.1.1 Thermal Resistance

    X.1.1.1 RCPS geofoam also functions as a thermal insulation. The thermal insulation properties of RCPS geofoam are as specified in Test Method C 578 and may impact the end use design of applications subject to different exposure conditions. Consult the RCPS geofoam manufacturer for specific recommendations.

    X.1.2 Solvent Exposure

    X.1.2.1 RCPS geofoam must be protected from petroleum based solvents and their vapors. Examples of these solvents are: gasoline, diesel fuel, concrete curing compound, coal tar pitch, and asphaltic mastic compounds.

    X.1.3 Equipment Traffic

    X.1.3.1 Equipment traffic that can impose contact pressures in excess of the allowable design stress for RCPS geofoam should be restricted. Protective materials such as sheathing or planks may be placed on the material to allow light rubber-tired equipment use.

    X.1.4 Buoyancy

    X.1.4.1 RCPS geofoam becomes buoyant when submerged and adequate ballast weight must be provided to resist expected uplift forces.

    X.1.5 Design

    X.1.5.1 The design and installation of RCPS geofoam is the responsibility of the user.

    X.1.5.2 RCPS geofoam can be supplied precut to specified dimensions to fit specific project needs. Desired shapes and sizes can also be field cut with a hot wire, saw, or other cutting tool.

This generic specification is intended for reference as a suggested method of practice until a standard becomes available through ASTM. The most current version is available from the Geofoam Research Center. Send requests to: grc@syr.edu or GRC, 220 Hinds Hall, Syracuse University, Syracuse, New York, 13244-1190.



Click here to see Table 1.