Strength Characteristics of Low Calcium Fly Ash Based …
Based on the mixture design process eighty one test cubes of 150x150x150mm of low-calcium fly ash-based geopolymer concrete were cast to study the effect of various parameters on compressive strength of low-calcium fly ash-based geopolymer concrete. Keywords: - Geopolymer concrete, Characteristic strength, Fly ash, Superplasticizer. I. …
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Chapter 3
The use of fly ash in portland cement concrete (PCC) has many benefits and improves concrete performance in both the fresh and hardened state. Fly ash use in concrete improves the workability of plastic concrete, and the strength and durability of hardened concrete. Fly ash use is also cost effective.
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(PDF) Development and Properties of Low …
fly ash or high-calcium fly ash, as it typically contains more than 20 percent of C aO. On the other hand, fly ash from the bituminous a nd anthracite c o als is referred a s ASTM Class F fly ash ...
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Effect of initial curing conditions on the durability …
Low-calcium fly ash (class F) according to ASTM C618 [20] was selected as the basic material for the preparation of geopolymer mortar mixtures. LCFA materials are more chosen than high calcium fly ash, with the thought that great amounts of calcium (class C fly ash) may affect the geopolymerization process.
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Using Fly Ash in Concrete
Low-carbon fly ash or the use of a better air-entraining agent at a higher-than-usual addition rate can control the problem of freeze-thaw durability. Advantages in Fresh Concrete Since fly ash particles are spherical and in the same size range as portland cement, a reduction in the amount of water needed for mixing and placing concrete can …
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Workability and strength of coarse high calcium fly ash geopolymer
2.2. Details of tests2.2.1.. Mix design and mixing of mortarAll geopolymer mortars were made with sand to fly ash ratio of 2.75. The NaOH of three concentrations viz., 10, 15 and 20 M and the sodium silicate to NaOH ratios by mass of 0.67, 1.00, 1.50, and 3.00 were used.In order to obtain the workable geopolymer mortar, a minimum base …
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Stabilization of Soft Clay by a Low-Calcium Fly Ash …
The current study investigated the stabilization efficacy of low-calcium fly ash (FA) geopolymer for soft clay. The influence of FA content, initial water content, and curing time on stabilization efficacy was investigated. ... The results indicated that the mechanical performance of the soft clay at high water content was greatly improved by ...
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Suitability of heat-cured low-calcium fly ash-based …
This paper discusses the advantages of using low-calcium fly ash (FA)-based geopolymer concrete (GPC) for precast applications when high early-age strength is required. Heat curing is known to be ...
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Enhancing performance and sustainability of GGBFS-based …
The usage of SCMs like groundnut shell ash (GSA), GGBFS, fly ash (FA), coconut shell ash (CSA), millet husk ash (MHA), and silica fume (SF) is well recognized …
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Geotechnical Properties of Low Calcium and High Calcium Fly Ash …
In this paper, a comparative study has been made for physical and engineering properties of low calcium and high calcium Indian fly ash. The grain size distribution of fly ash is independent of lime content. Fly ash particles of size >75 μm are mostly irregular in shape whereas finer fractions are spherical for low calcium fly ash. For high calcium fly ash, …
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Fly Ash
Sometimes fly ashes may also contain many small spherical particles within a large glassy sphere, called pherospheres. The exterior surfaces of the solid and hollow spherical particles of low-calcium oxide fly ashes are generally smooth and better defined than those of high-calcium oxide fly ashes which may have surface coatings of …
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Properties of high-calcium and low-calcium fly ash …
This study presents the properties of a recycled aggregate geopolymer mortar made with a blend of high-calcium fly ash (HCF) and low-calcium fly ash (LCF). An experimental study was divided into two series. ... (1–2% fly ash by weight) was added. After mixing, the geopolymer samples were left at ambient temperature for 1 h before heat curing ...
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The effects of calcium content of fly ash on hydration and
According to the difference in calcium content, fly ash is divided into high-calcium fly ash (C-class FA, abbreviated to HFA) and low-calcium fly ash (F-class FA, abbreviated to LFA) during actual engineering practice (Du et al., 2022). In general, HFA possessed higher reactivity than LFA in the hydration process of cement, which was …
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Materials | Free Full-Text | Experimental Investigation on …
The challenges of handling user-hostile alkaline solutions in the conventional alkali-activated binders (AAB) have initiated the development of "just add water" or one-part solid-based AAB systems. This paper aims to present a preliminary investigation on the development of one-part ambient-cured alkali-activated binders produced by …
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Review A review on fly ash high-value synthesis utilization …
As a common industrial solid waste, fly ash requires proper processing and utilization to alleviate environmental pressure. In contrast to earlier low-value treatment methods for fly ash, such as its use in construction materials, it is more practical to explore the high-value utilization of fly ash, considering its elemental ingredient and …
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Characteristics and applications of fly ash as a sustainable
Fly ash is a man-made volcanic material. The definition of volcanic fly ash is "silicate or aluminosilicate material, which possesses weak or non-self-cementing ability, but in the finely divided state and damp environments at room temperature, it reacts with Ca(OH) 2 to form gel products" (Dunstan, 1989).There are many factors affecting the …
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Fly Ash Pollutants, Treatment and Recycling | SpringerLink
3.2.1 Coal Fly Ash. Coal FA is a predominantly inorganic residue obtained from the flue gases of furnaces at pulverised coal power plants. When coal is burnt, the minerals entrained in the coal are thermally transformed into chemical species that are reactive or could be chemically activated, for example, by the addition of calcium …
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Effect of High-Speed Mixing on Properties of High …
This research studied the effect of mixing when used a high-speed mixer (1,000rpm) at various mixing time on the setting time, compressive strength, mineral composition, …
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Use of Cement and Bottom Ash in Deep Mixing Application …
The deep mixing method is considered one of the most popular ground improvement techniques, which cement is commonly used as a cementitious material. However, the use of cement resulted in high cost and high carbon footprint. Utilizing bottom ash, a by-product from electricity power plant, as a green stabilizer material is of …
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The Influence of Fly Ash and Slag on the Mechanical …
The use of geopolymer as a cementitious material for geopolymer concrete (GPC) is beneficial for the sustainable development and green transformation of the …
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Drying shrinkage, strength and microstructure of alkali-activated high
This paper aims to investigate drying shrinkage, strength and microstructure of alkali-activated high-calcium fly ash (AAHF) paste by using FGD-gypsum (FGD) and dolomite (DLM) as expansive additives. The 10 M sodium hydroxide combined with sodium silicate solutions were used as alkaline activator for all mixes. …
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Alkali-Activated Controlled Low-Strength Material Utilizing High …
AbstractThis study investigated the performance of alkali-activated, cement-based controlled low-strength materials (CLSMs). The CLSM was produced by mixing fly ash, steel slag, sodium hydroxide, and water with bottom ash (BA) aggregate. Properties of ...
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Flexural Behavior of Low Calcium Fly Ash Based …
The main parameters affecting the fly ash geo-polymer mixtures are the content of cilium, concentrations of alkaline solutions, and curing method. In GPC, the low calcium fly ash is preferred because high calcium poses the risk of flash setting before casting the elements (Antoni et al., 2020).
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LOW CALCIUM FLY ASH GEOPOLYMER CONCRETE
The calcium content of slag is approximately 42% while of low calcium fly ash is 1.5%. The mix proportion of binder, that is 95% fly ash and 5% slag, resulted the increase of fly ash binder
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A study on the synthesis and performance evaluation of fly …
Different supplementary cementitious materials (SCMs) like fly ash (FA), silica fume (SF), and slag are used to partially replace traditional raw materials like …
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Development of angular-shaped lightweight coarse aggregate with low
Low-calcium fly ash is the least commonly used fly ash among low and high-calcium fly ashes, owing to its lack of self-cementitious capabilities [4]. Producing environment-friendly fly ash aggregate using a sustainable and low-cost technique is the best solution to overcome the problems related to safe disposal of low-calcium fly ash …
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Fly Ash
In Europe, the use of high-calcium fly ashes HCFA(s) blended directly into concrete is not defined by a specific regulative frame as in the case of siliceous fly ashes where there is the standard EN 450-1:2005, but there are definitions in European standards for cement ( 2007, EUROGYPSUM-ECOBA-VGB 2005).Therefore, the …
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Effect of High-Speed Mixing on Properties of High Calcium …
This research studies the effects of mixing time, with a high-speed centrifuge mixer (1,000 rpm), on the setting and hardening properties of high calcium fly ash …
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The potential of FBC fly ashes to reduce CO 2 emissions
Siriruang, C., Toochinda, P., Julnipitawong, P. & Tangtermsirikul, S. CO 2 capture using fly ash from coal fired power plant and applications of CO 2-captured fly ash as a mineral admixture for ...
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Compressive Strength and Workability Characteristics of …
In this research study, Low-calcium (ASTM Class F) Fly ash obtained from Manjung Power Station, Lumut, Perak, Malaysia was used as a source material for the synthesis of
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