Mix Design

Is it appropriate to add fly ash to the cement and water slurry for Geofill cellular concrete?

  • Fly ash added to the cement does not adversely affect the basic hardened state of Geofill cellular concrete. Infusing and supporting the material with the air cell system is a mechanical action and is not problematic with fly ash or admixture concrete chemistry. Note: some fly ash mixes may take longer to set than pure Portland cement applications. High carbon content fly ash such as typical “bottom ash” should be generally avoided in most cellular or plain concrete mixes.

Do Geofill cellular concrete mix designs contain either fine or coarse aggregate?

  • Geofill LD Hybrid may also contain normal or lightweight, fine and/or coarse aggregates. Geofill LD and Geofill LD Pervious mix designs are designed to create a product with a low density and resultant relatively lower compressive strength (when compared to plain concrete). The typical density range is 20-60 lbs. / cu. ft. which develops a corresponding compressive strength range of 50 PSI - 930 PSI. When higher compressive strengths are required, the addition of fine and/or coarse aggregate will result in a stronger cellular concrete with resultant higher densities.
  • For more information, view Geofill LD Hybrid, Geofill LD and Geofill LD Pervious

What is the correct water to cement ratio for cement water slurry?

  • A .5 water to cement ratio slurry consisting of two parts cement to one part water is typically used as a base mixture for these products. The water cement ratio is varied according to specific project requirements. We should note that Geofill obtains its natural fluidity from the air bubble structure, not from excess water content.