Investigation on Strength Enhancement of Cement Paste Using Biogenic Nanoparticles

The present study attempts to understand the effect of hydrophobic water-dispersed biogenic silver nanoparticles (AgNPs) over commercial silica nanoparticles (SiNPs) on the fresh and hardened properties of cement paste. The average particle size of AgNPs is 10 nm, whereas that of reference SiNPs is 12 nm. The effect of AgNPs replacing 0.5 and 1% of binder material has been studied and compared with the effect of SiNPs. It is observed that the addition of AgNPs does not enhance water requirement for consis-tency; neither does it adversely impact the setting time. The results on compressive strength of cement paste show higher initial and long term strength for specimens blended with AgNPs with the percentage increment for 3-28 days strength ranging between 40 and 43%, whereas the same for SiNPs ranges from 26 to 29%. For optimized binary mixes with Alccofine, the strength increment from 3 to 28 days ranges from 8 to 30% for AgNPs, whereas for SiNPs it ranges from 10 to 43%. In case of binary mix with Fly Ash C, addition of AgNPs improves strength in the range from 31 to 40%, whereas SiNPs improves strength from 10 to 41%. The strength observed with AgNPs is comparable with those of commercial SiNPs with an addi-tional advantage of reduced water demand for consistency, thus making it an attractive alternative for possible applications in mortar and concrete.Copyright (c) 2022 Elsevier Ltd. All rights reserved.Selection and peer-review under responsibility of the scientific committee of the International Confer-ence on Advances in Construction Materials and Structures.