Utilization of Waste and By-Products in RCC Material
When required per engineering specification, fly ash can be augured from an Auxiliary Silo adjacent to the Rapid twin-shaft Continuous Mixing Plant as a replacement for a portion of the Portland cement content when mixing RCC, CTB, or Soil cement. The use of a pozzolanic ash in the material greatly improves the strength and durability of concrete.
Use of fly ash as a partial replacement for Portland cement is generally limited. See the below archive from the US Department of Transportation - Federal Highway administration:
In some applications it can replace up to 30% by mass of Portland cement, can add to the concrete's final strength, and increase its chemical resistance and durability. Due to the spherical shape of fly ash particles, it can also increase workability (retard drying times) of cement while reducing water demand. The replacement of Portland cement with fly ash reduces the greenhouse gas "footprint" of concrete. The production of one ton of Portland cement produces approximately one ton of CO2. Fly ash, a waste product of burning coal, can be used without adding any further CO2 emission into the atmosphere. Substituting any portion of cement with fly ash in a given application will significantly reduce carbon emissions associated with construction.