The results showed the presence of low calcium, high silica and alumina content in fly ash whereas high calcium content was observed in OPC. Fig. 1 shows the XRD analysis …
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High calcium fly ash (HCFA) is less effective in comparison to low calcium fly ash in controlling sulphate attack in concrete [1], [2], [3], [4].In fact, high calcium fly ash has shown …
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The Afşin-Elbistan thermal power plant, which is located in Turkey, is a lignite burning thermal power plant with a capacity of eight units in two plants and an installed …
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Fly ash for sustainable construction: A review of fly ash concrete and its beneficial use case studies ... The class F FA is a byproduct of bituminous coal combustion. The iron, …
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The compressive strengths of composite with 3.75% silica fume immersed in 5% magnesium sulfate solution and 3% sulfuric acid solutions were substantially higher than the …
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The aim of the study was to generate rules for the prediction of the chloride resistance of concrete modified with high calcium fly ash using machine learning methods. The …
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To understand the formation mechanism of high-calcium fly ashes, the mineralogical, physical, and chemical properties of several high calcium fly ashes and their different density fractions …
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During the 80s, several workers highlighted the distinct behavior of Class C fly ashes during hydration. Marsh and Day [14] for example, compared the hydration of a Class C …
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According to ASTM C618 [91], a fly ash containing low alkali and low calcium is classified as class F and those with high alkali and high calcium content belong to class C. It …
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On, the other hand, the brittleness promoted by the addition of excess silica content in the mix might be the reason for the later [51]. 3.3. Mineralogical and microstructural …
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The efficiency of ternary blends containing high-calcium fly ash and slag in mitigating alkali-silica reaction (ASR) was evaluated. The concrete prism expansions showed …
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To our knowledge, material properties and composition of fly ash with relatively higher calcium influencing its performance in concrete has been rarely reported. This work …
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Mineral admixtures such as silica fume, fly ash, and ground granulated blast-furnace slag improve the engineering properties and performance of concrete when they are …
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High-calcium fly ashes, classified as Cla ss C by ASTM International (ASTM) C618 definition, are often excluded as a means to mitigate alkali silica reactions (ASR) in concrete. This is …
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The minimum combined content of SiO 2, Al 2 O 3, and Fe 2 O 3 of 50% was detected for the Class C fly ash, with a high calcium content of 31.0 wt%. The median particle …
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The use of high-calcium fly ash (H-FA, Class C) produced by burning the lignite or sub-bituminous coal in Portland cement materials is limited due to problems such as the …
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Therefore, in this paper, calcium alginate hydrogel bead was prepared, and the synergetic influence of calcium alginate hydrogel and CA on crack-healing performance of …
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Influence of silica fume content on temperature increase of fly ash-silica fume paste (designations according to Table 4). Figures - available via license: Creative Commons Attribution 4.0 ...
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During compound activation, when the amount of calcium hydroxide exceeds that of calcium sulfate, the high OH-content creates a highly alkaline environment, accelerating fly …
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Two high-calcium fly ashes (designated here as T f and T k) were selected from a total of eight ashes coming from Ptolemais area. The principal aim, during the selection …
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Overall, increases in either silica or alumina content appear to shorten the setting time of high calcium-based systems unlike conventional geopolymer systems where increasing Al 2 O 3 accelerates setting. The …
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2.1 Materials and Equipment. The brown coal fly ash was supplied from Germany; it was treated with water, homogenized and ground by the manufacturer. The chemical …
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Single and binary solid alkali activators were used to activate high calcium fly ash. The alkali activators were either solely sodium metasilicate (Na2 SiO 3) or a combination of …
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to develop improved strength under ambient curing [20]. The inclusion of silica fume into low calcium fly ash geopolymer optimizes the microstructure and yielded higher strength [21-24]. …
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The present study has High Calcium Fly Ash (HCFA) and silica fume as the source material for the geopolymer mortar. In this experiment, it is proposed to mix HCFA with silica fume …
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Although elevated temperature curing can increase the compressive strength of alkali-activated mortar, its field applications are still limited. In this study, alkali-activated mortars were prepared using high …
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High-calcium fly ash expansion as a stand-alone binder can be stopped by using a silica fume additive. For the fly ash at the Berezovskaya Power Plant, this content is 40% of the fly ash mass [16]. With a lower amount …
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Class F fly ash is pozzolanic brought out from either anthracite or bituminous burning of coal. The total amount of SiO2, Al 2 O 3, and Fe 2 O 3 must be greater than 70%. …
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High-calcium fly ashes, classified as Class C by ASTM International (ASTM) C618 definition, are often excluded as a means to mitigate alkali–silica reactions (ASR) in concrete. This is …
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The reactivity of silica in the hydration of fly ash-cement blends was found to hold a ... (>20%) class C fly ash was found to be more reactive to water than that in the low-calcium …
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