Effect of various parameters on the workability and strength properties of geopolymer concrete

Nutakki Sai Ketana,V Srinivasa Reddy,S Shrihari,M V Seshagiri Rao,S Tummala,S Kosaraju,P Bobba,S Singh

doi:10.1051/e3sconf/202130901102

Nutakki Sai Ketana, V Srinivasa Reddy + Show 6 more

Open Access

https://doi.org/10.1051/e3sconf/202130901102

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Abstract

In the present study, effect of various molarities of NaOH, various fly ash content and alkaline activator solution (AAS) / fly ash(FA) ratios on the workability of geopolymer concrete(GPC) are studied along with the effect of use of Na2SiO3/NaOH and K2SiO3/KOH as alkaline activator solutions and various fly ash contents on the compressive strength of geopolymer concrete mixes. Observations shows that both Na2SiO3/NaOH and K2SiO3/KOH gives better performance for different molar, AAS/FA and oxide ratios. Class C GPC has better performance than Class F GPC. It was found that the increase in molarity decreases workability of geopolymer concrete. Also, the workability increases with increase in fly ash (FA) content and AAS/FA ratio in geopolymer concrete. Compressive and split tensile strengths decrease with increase in fly ash content.

Highlights

In India, coal with an ash level of about 40% is mostly utilised for thermal power generation
In low calcium fly ash based geopolymer concrete mixes, sodium aluminosilicate hydrate (N-A-S-H) gel is the main reaction product, whereas calcium silicate hydrate (C-SH) and calcium aluminosilicate hydrate (C-A-S-H) gels coexisted with sodium aluminosilicate hydrate (N-A-S-H) gel as the main reaction products in high calcium fly ash When cured at room temperature, the high CaO concentration improves the strength development
Due to the high calcium concentration available in Class C raw fly ash material, geopolymer concrete (GPC) manufactured with Class C fly ash has a greater compressive strength at ambient temperature than GPC created with Class F fly ash

Summary

Introduction

In India, coal with an ash level of about 40% is mostly utilised for thermal power generation. Massive amounts of fly ash (FA) are produced in thermal power plants, generating a slew of disposal issues. For almost 60 years, fly ash has been utilised as a mineral additive component in Portland pozzolan mixed cement. He used the notion of aluminosilicate gel binding action to create inorganic polymer of aluminosilicates by combining silica and alumina from specially treated clay (metakaolin). Portland/pozzolanic cements, do not use calcium-silicatehydrates (CSHs) for matrix formation and strength, instead relying on the polycondensation of silica and alumina precursors. Because GPCCs are a novel class of materials, unlike traditional cement concretes, traditional mix design techniques are not typically relevant. The creation of GPCC mixes necessitates a comprehensive review of the components available

Geopolymer synthesis

Formulating the GPCC mixes

Effect of different types of Alkaline activator solutions

Conclusions

Findings

A Review on Flexural Behavior of RCC Beams