Mechanical, Permeability, and Photocatalytic Properties of White Ultrahigh-Performance Concrete with Nano-TiO2

White ultra-high performance concrete (WUHPC) was prepared with limestone powder (LP), silica fume (SF), and metakaolin (MK) to meet low carbon requirements. The influence of the mineral admixture on fluidity, strength, and whiteness of WUHPC was studied by orthogonal experiments and variance analysis. The effects of nano-TiO2 (NT) on fluidity, strength, whiteness, impermeability, and the photocatalysis of WUHPC were also investigated. Results shown that the fluidity of WUHPC was decreased with increased concentration of NT. The compressive and flexural strength of WUHPC reached 198 MPa/44.4 MPa when the NT content was 1%. The whiteness of WUHPC increased and then decreased with increasing NT content. The water absorption of WUHPC continuously increased when the NT content exceeded 1%. The photocatalytic rate of WUHPC continuously increased to 18 times greater when NT increased from 3% to 10%. (c) 2022 American Society of Civil Engineers.