Effect of nano TiO2 on mechanical properties and microstructure of concrete

Abstract

Nano TiO2 (NT) has a wide range of applications due to its physical and chemical properties, it has received attention from researchers as well as the industry community. In the present study, mechanical properties of concrete were investigated with the use of different percentages of NT along with the industrial waste named fly ash class F (FA). Nano TiO2 particles are added in ordinary Portland cement (OPC) in different percentages 1, 2, 3, 4, and 5 and with 20 percent of FA. The constant 0.4 water to cement ratio (w/c) was used throughout the study. The results indicate that the NT acts as filler in the space and improves the compressive strength at 28 days. The improvement was observed in early age compressive strength at 3 days of NT concrete compared with control concrete. The results of flexural strength and split tensile strength were compared with control concrete and are found satisfactory. NT particles could enhance the pore structure of the concrete due to its extremely low particle size. The investigation of microstructure of concrete was done by scanning electron microscopy (SEM) and it was observed that the microstructure of concrete with NT improved compared to conventional concrete. The concrete with 4% nano TiO2 and 20% FA was found to be optimum among all the combinations studied.