Performance and Microstructural Evaluation of Rice Husk Ash–Ground Granulated Blast Furnace Slag–CFBC Fly Ash Mixtures Produced as an Eco-Cement

This paper enumerates strength gain efficiency of Rice Husk Ash (Rha) and Ground Granulated Blast Furnace Slag (Gbbfs) blend in Self-Compacting Concrete (SCC). From the precious studies carried by the authors it was observed that optimal use of Rha+Ggbfs in low and medium strength concretes imparts initial strengths and also later strengths. In low and medium strength SCC mixes, Ggbfs replaces OPC optimally (30%) and Rha replaces Ggbfs optimally (3%) but in case of high strength SCC mixes, RHA replacing Ggbfs does not offer the required workability or strength so instead of replacing Ggbfs by certain amount, Rha is added to the SCC. It was found that GGBFS does not yield the required workability so RHA is added to GGBFS based SCC. So after various trial mixes it was found that 25% GGBFS by weight of OPC and 5% RHA by weight of GGHFS is added to OPC. It was observed that 5% RHA addition to OPC made with 25% Ggbfs gives desired workability and strength. Due to addition of GGBFS to SCC will enhance the later age compressive strength but early age compressive strength decreases while the desired workability is controlled using SP appropriately. In M60 GGBFS+RHA based SCC, the strength increase at 3 days is nearly 33% and the compressive strength at 28 days decreased by 10%. Similarly tensile strength in a GGBFS and RHA admixed SCC increases by around 27% in M60 grade.

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Sustainable geopolymer concrete using ground granulated blast furnace slag and rice husk ash: Strength and permeability properties

Journal of Cleaner Production ◽

10.1016/j.jclepro.2018.08.313 ◽

2018 ◽

Vol 205 ◽

pp. 49-57 ◽

Cited By ~ 41

Author(s):

Ankur Mehta ◽

Rafat Siddique

Keyword(s):

Blast Furnace ◽

Rice Husk ◽

Blast Furnace Slag ◽

Rice Husk Ash ◽

Geopolymer Concrete ◽

Granulated Blast Furnace Slag ◽

Furnace Slag

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Novel Approach for Suppression of Ettringite Formation in Sulfate-Bearing Soil Using Blends of Nano-Magnesium Oxide, Ground Granulated Blast-Furnace Slag and Rice Husk Ash

Applied Sciences ◽

10.3390/app11146618 ◽

2021 ◽

Vol 11 (14) ◽

pp. 6618

Author(s):

Khaled Ibrahim Azarroug Ehwailat ◽

Mohd Ashraf Mohamad Ismail ◽

Ali Muftah Abdussalam Ezreig

Keyword(s):

Blast Furnace ◽

Magnesium Oxide ◽

Rice Husk ◽

Blast Furnace Slag ◽

Rice Husk Ash ◽

Soil Samples ◽

Ettringite Formation ◽

Granulated Blast Furnace Slag ◽

Furnace Slag ◽

Gypseous Soil

The treatment of sulfate-bearing soil with calcium-based stabilizers such as cement or lime often results in ettringite formation, consequently leading to swelling and strength deterioration. Ettringite formation has negative environmental and economic effects on various civil engineering structures. This study was conducted to investigate the use of different materials (nano–magnesium oxide (M), ground granulated blast-furnace slag (GGBS), and rice husk ash (RHA)) for gypseous soil stabilization to prevent ettringite formation. Various tests were performed, including flexural strength, unconfined compression strength, linear expansion, and microstructure analysis (SEM/EDX), on lime (L)-, (M)-, (M-RHA)-, (M-GGBS)-, and (M-GGBS-RHA)-stabilized gypseous soil samples to determine their properties. The results indicated that the swelling rates of the soil samples mixed with 20% M-RHA, M-GGBS, and M-GGBS-RHA binders were much lower (less than 0.01% of volume change) than those of the soil samples mixed with 10% and 20% lime-stabilized binders after a curing period of 90 days. Meanwhile, the strengths of the soil samples mixed with 20% of M-RHA, M-GGBS, and M-GGBS-RHA soil specimens after soaking of 90 days were obviously higher (with a range from 2.7–12.8 MPa) than those of the soil samples mixed with 20% of lime-stabilized binder. The SEM and EDX results showed no ettringite formation in the M-RHA-, M-GGBS-, and M-GGBS-RHA-stabilized soils. Overall, the test results proved the potential of M-RHA, M-GGBS, and M-GGBS-RHA as effective soil stabilizers.

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