Statistical significance of the influence of nano-TiO2 on WPC, PPC, and OPC cement mortars

Abstract Durability of cement mortars and concrete is of significant importance in the field of concrete technology. Self-cleaning ability affects durability of cementitious compositions wherein Nano TiO 2 (NT) is widely utilized in research worldwide as a popular photocatalyst. In this study, NT was applied to the cement mortars in three methods: intermixed (IM), fresh cast coat (FC), and hardened coat (HC) to three types of cements and the color removal efficiency of each combination is identified. ANOVA technique was used to analyze and understand the significance of the variance in color removal efficiency with respect to change in the dosage of NT, type of cement and NT application method. The variance analysis results suggest that White Portland Cement (WPC) exhibits increased variability in color removal efficiency, the Portland Pozzolana Cement (PPC) stabilizes at higher dosages, and Ordinary Portland Cement (OPC) demonstrates an initial increase followed by a decrease in variability. Across all the combinations, the NT dosage had a significant impact on the color removal efficiency, while the cement type did not significantly affect it. The type of NT application method significantly affected the color removal efficiency among all dosages and cement types, OPC having a greater effect than the other cement types.