Durability studies of nano-engineered fly ash concrete. (10th January 2019)

• Record Type: Journal Article
• Authors: Singh, L.P.; Ali, D.; Tyagi, I.; Sharma, U.; Singh, R.; Hou, P.
• Is Part Of: Construction & building materials. Volume 194(2019)
• Page Start: 205
• Page End: 215
• Publication Date: 2019-01-10
• Subjects: Silica nanoparticles -- Sulphate -- Carbonation -- Service life -- CH and C-S-H; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2018.11.022
• Languages: English
• ISSNs: 0950-0618

Abstract

Graphical abstract: Highlights: SNPs incorporation in concrete leads to the enhanced service life and durability. SNPs incorporation leads to significant reduction in carbonation depth (∼73%). SNPs incorporation leads to significant reduction in sulphate attack (∼39%). SNPs incorporation lead to attain early age strength in FA mix concrete specimens. SNPs due to its higher pozzolanic activity, lead to the formation of additional C-S-H. Abstract: Mechanical and durability properties of nano-engineered fly ash concrete have been carried out using various concrete mixes containing 30–50% fly ash (FA), 3% silica nanoparticles (SNPs) and 6% silica fume (SF) at constant water/cement (w/c) ratio of 0.29. Durability parameters i.e. carbonation (2% CO2, 20 °C, 65% RH) and sulphate attack (5% magnesium sulphate) were investigated using these specimens after exposing them up to 180 days. Long-term carbonation results revealed that SNPs incorporated mixes show a reduction of carbonation depth up to 73% with respect to control specimens containing 30% FA. Similarly, SNPs incorporated specimens show significant resistance towards the sulphate attack of about 39% as compared to control specimens. For the comparison purpose, SF containing specimens were also evaluated, however, higher resistance were observed for SNPs incorporated concrete specimens. Diffusion coefficient and service life of SNPs incorporated specimens were studied using Meta and Demis model, revealed exponential enhancement in the service life of SNPs incorporated concrete mixes.