Strength, water permeability, and heat evolution of high strength concrete made from the mixture of calcium carbide residue and fly ash

This study evaluates the mixture of ground calcium carbide residue (GCR) and ground fly ash (GFA) for use as a new cementing material to produce high strength concrete. Ordinary Portland cement was used as an activator to promote the reaction between GCR and GFA. Compressive strength, modulus of elasticity, heat evolution, and durability in term of water permeability of concrete were investigated and compared with concrete made from ordinary Portland cement (OPC concrete). The results showed that GCR–GFA mixture, despite containing no Portland cement, had a high potential to be used as a new cementing material for producing high strength concrete having a compressive strength that exceeds 50 MPa. Furthermore, the compressive strength of GCR–GFA concrete containing 20% Portland cement (used Portland cement of 110 kg/m3) could be as high as 67 MPa or 95% of OPC concrete at 28 days and increased up to 73 MPa at 90 days or 90% of OPC concrete (used Portland cement of 550 kg/m3). The GCR–GFA concretes with and without Portland cement had moduli of elasticity similar to OPC concrete i.e., they increased with the compressive strength. In addition, water permeability of high strength concrete made from GCR–GFA mixture was equal to or slightly lower than OPC concrete. Finally, concrete made from GCR–GFA mixture had much lower heat evolution than OPC concrete.