Strength and Durability of Concrete Containing Ceramic Waste Powder and Blast Furnace Slag

The replacement rates of portland cement by ceramic waste powder (CWP) are generally limited to few percentages (i.e., less than 10%), as increased additions lead to inferior concrete strength and durability. This paper assesses the importance of blending CWP with blast furnace slag (BFS) to foster synergistic pozzolanic reactions and reinstate strength development despite increased cement replacement rates. Tested binders contained different cement-CWP-BFS proportions, while the evaluated properties included the compressive, splitting tensile, and flexural strengths in addition to the modulus of elasticity, freeze/thaw resistance, and thermal transmittance. Test results showed that concrete strength and durability gradually degraded when the cement was partially replaced by 10%-20% CWP, given the dilution effect that alters hydration reactions and overall porosity. Yet, the concrete properties significantly improved when the CWP and BFS materials were both incorporated in the same binder, indicating the occurrence of synergistic pozzolanic reactions that refined the matrix microstructure. Hence, concrete prepared with ternary binder containing 50% cement, 15% CWP, and 35% BFS exhibited durability and strength properties at 56 days comparable to the control mix made with 100% cement.