Influence of nano TiO2 on strength and durability properties of geopolymer concrete

Abstract

Geopolymer concrete (GPC) is treated as an ecologically pure construction material because cement is completely retrieved by pozzolanic materials that are abundant in alumina and silica. GPC is actuated with alkaline liquids to begin as a binder in concrete. Geopolymer concrete evince many outstanding properties just as rapid strength, less shrinkage, and less creep, better resistance against sulphate and chloride attacks. The current review is to explore the effect of nano titanium dioxide (nano-TiO 2 ) on fly ash based geopolymer concrete (FAGPC) with oven curing at 60 0 c for 48 hrs. As an initial study, GPC with 10 M was carried out for dissimilar ratios of sodium silicate (Na 2 SiO 3 ) to sodium hydroxide (NaOH) solutions between 1.5 and 3.5. Out of all mixes, alkaline activator ratio harmonize to the highest compressive strength was ascertained at 2.5. This ratio was kept constant for further study in GPC carried out by replacing fly ash with nano TiO 2 between 1% and 5%. For all mixes of GPC with and without nano titanium dioxide, mechanical and durability properties were observed and evaluated. The test results depict that, percentage increase of nano TiO 2 , gives rise to decline in workability and improves strength properties of concrete. The maximum strength enrichment was noticed when 5% of nano-TiO 2 was incorporated in GPC. As percentage of nano TiO 2 hiked in GPC, the results of RCPT, Water absorption and Sorptivity decreased. All these GPC specimens are immersed individually in 5% magnesium sulphate and 5% sodium chloride to know the resistance of geopolymer concrete against sulphate and chloride attacks. Results of this study concluded that increase in nano TiO 2 percentage gives better performance against sulphate and chloride solutions. Change in microstructure and mineral phases of reference geopolymer concrete samples and maximum strength obtained geopolymer concrete samples containing nano TiO 2 was investigated using SEM and XRD analyses.