Specification for Geofill LD Hybrid Low Density Controlled Low Strength Material For Filling Abandoned Pipes & Structures


This work consists of providing Geofill LD Hybrid, a heavier than water, Low Density Controlled Low Strength Material to fill abandoned pipes or other structures at the location shown in the plans in accordance with the details in the plans and these specifications.

  • Portland cement shall comply with ASTM C150 (Type I, II or III).
  • Fly ash shall be Class C or Class F and compatible with foaming agent.
  • Aggregate shall be fine or coarse sand, limestone screenings, or other aggregate as approved by pre-formed foam manufacturer.
  • Water shall be free from deleterious substances.
  • Foaming agent shall be Geofill Concentrate (Phone: 888.820.3455) conforming to ASTM C796.
  • Admixtures for water reducing, retarding, accelerating, and other specific properties may be used when recommended by the manufacturer of the foaming agent.
  • Geofill LD Hybrid shall have the following properties:
    • Range of Cast Density, PCF 65-85
    • Minimum Compressive Strength (28 Days), PSI 50
    • Flow Consistency per ASTM D6107 Greater than 6”
  • This product is available in strengths up to 800 PSI.
  • Mix design for Geofill LD Hybrid, including materials to be used and their sources.
  • Resume of contractor showing qualifications as specified below, including qualifications of contractor’s superintendent and/or foreman.
  • Description of equipment and placement methods to verify compliance with specifications.
  • Foam generating equipment shall be used to produce a predetermined quantity of pre-formed foam which shall be mixed and blended with cementitious slurry. Equipment shall be calibrated to produce a consistent foam with stable, uniform cellular structure.
  • Geofill LD Hybrid shall be produced utilizing specialized automated proportioning, mixing, and foam producing equipment, which is capable of meeting the specified properties.
  • Avoid excessive handling of the material. After sufficient mixing of the foam with slurry, the material shall be conveyed promptly in its final location. Concrete piston pumps may be used to place this material.
  • All equipment used must be approved by the foam manufacturer.
  • All bulkheads and injection points installed shall be capable of withstanding a minimum of 30 PSI or the allowable maximum pressure, whichever is greater and shall be water tight.
  • Injection ports and pipes must be securely installed and be able to receive a minimum 2” male threaded NPT.
  • Space injection points at intervals to allow adequate inspection ports so material may be forced from one injection point to the next at pressures below maximum allowable pressure.
  • All water and other residual materials must be removed from pipe prior to initiating filling procedure. If required, de-watering shall be continuous during installation of cellular concrete.

Contractor shall have a record of experience and quality of work placing low density controlled low strength material to fill abandonments that is satisfactory to the Engineer including the following:

  • Shall be capable of developing a mix design, batching, mixing, handling, and placing low density controlled low strength material.
  • Shall be regularly engaged in the production and pumping of low density controlled low strength material for filling abandoned pipes or other structures.
  • Shall have satisfactorily completed during the last twelve (12) months at least five (5) similar projects.
  • Workers, including the contractor’s superintendent and/or foreman, shall be fully qualified to perform the work and have had previous experience in production and placement of low density controlled low strength material under similar conditions.
  • A minimum of four (4) 3”x 6” cylinders shall be molded for each shift of operation.
  • Geofill LD Hybrid may be tested at any age after three (3) days for compressive strength. At least two (2) specimens from each set should be tested at 28 days in accordance with ASTM C-495.
  • Contractor shall record and measure wet cast densities at the point of placement regularly. Mix shall be adjusted as required to obtain the specified cast density at the point of placement.
  • Contractor shall record and measure flow consistency regularly in accordance with ASTM D6107.
  • Geofill LD Hybrid shall be paid for at the contract unit price per cubic yard for material produced.
Geofill LD Hybrid - Abandoment Fill Specifications pdf 21.07 KB