Alkali and sulfate effects on mechanical properties and microscopic mechanisms of slag and fly ash geopolymers

Scientific Reports, Год журнала: 2025, Номер 15(1)

Опубликована: Янв. 29, 2025

Aiming at the problem that it is difficult to realize low-cost, high-performance and large-scale utilization of cementitious materials prepared from bulk solid wastes, this paper constructs a set composite system based on alkaline activation slag fly ash (FA) by calcium carbide (CCS) synergistic sodium sulfate (Na2SO4) as chemical dopant. The influence factors such waste type, mixing ratio, Na2SO4 content mechanical properties systems was investigated assessing compressive strength analyzing microstructure using XRD, SEM-EDS, FTIR. test results indicate CCS exert significant influences system. acts an alkali activator, enhancing system's hydration with optimal dosage 25%. Low also promotes hydration, but higher concentrations disrupt internal structure post-coagulation, 6%. Projection Pursuit Regression (PPR) prediction model can fit actual experimental data very well, which provides feasible method for proportion design all-solid-waste systems.

Язык: Английский

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A comprehensive review of carbon dioxide capture, transportation, utilization, and storage: a source of future energy

Environmental Science and Pollution Research, Год журнала: 2025, Номер unknown

Опубликована: Март 25, 2025

Язык: Английский

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Optimizing recycled aggregate concrete performance with chemically and mechanically activated fly ash in combination with coconut fiber

Scientific Reports, Год журнала: 2025, Номер 15(1)

Опубликована: Март 18, 2025

As a matter of fact, although RCA is inferior to that NA (natural aggregate) in terms performance, currently being used extensively concrete production as sustainable solution due global increasing construction waste. To overcome these limitations, several mechanisms and supplementary cementitious materials (SCMs) have been investigated the recent past. This study investigates combined effect natural fiber coconut (0%, 0.5%,1%,1.5% 2%) activated fly ash (mechanically chemically) on performance recycled aggregate (RCA). Four compositions were studied: control group with varying percentages no ash, second 30% inactive third mechanically fourth chemically ash. The findings revealed addition 1.5% CF increased compressive strength by 25%, tensile 17% for 100% mix, While losses same mix are 7.18% after one month 22.14% three months acid exposure. Scanning electron microscopy further validates enhanced packing density effective crack filling optimized mixes, highlighting their superior performance. approach holds significant potential advancing development pathways high-performance structural concrete, particularly regions prioritizing green building solutions.

Язык: Английский

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Properties and Optimization Process Using Machine Learning for Recycling of Fly and Bottom Ashes in Fire-Resistant Materials

Processes, Год журнала: 2025, Номер 13(4), С. 933 - 933

Опубликована: Март 21, 2025

Significant amounts of coal fly and bottom ash are generated globally each year, with especially large quantities accumulating in landfills. In this study, were used to create fire-resistant materials. A mix 30 wt% gypsum, 9.5 vermiculite, 0.5 polypropylene fibers was used, maintaining a constant water-to-solid ratio, varying ash/bottom ratios (40/20, 30/30, 20/40). The density, as well various mechanical properties (compressive strength, flexural surface hardness), fire insulation capacity, leaching behavior both ashes evaluated. When comparing the 40/20 20/40 compositions, slight decrease density observed; however, compressive strength dropped drastically by 80%, while decreased slightly due action fibers, resistance 8%. Neither presented any environmental concerns from standpoint. Additionally, historical data materials different wastes previous works train machine learning models (random forest, gradient boosting, artificial neural networks, etc.). Compressive predicted. Simple parameters (density, water/solid ratio composition for thickness resistance) input models. Both regression classification algorithms applied evaluate models’ ability predict strength. Regression reached r2 up about 0.85. results rating (FRR) showed high accuracy (96%). prediction is not good prediction, but 99% some

Язык: Английский

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Reducing CO2 Emissions in Urban Infrastructure: The Role of Siliceous Fly Ash in Sustainable Mortar Design

Sustainability, Год журнала: 2025, Номер 17(11), С. 4835 - 4835

Опубликована: Май 24, 2025

The incorporation of industrial by-products such as fly ash (FA) into cementitious materials plays a vital role in promoting environmental sustainability during cement production. This study evaluates the feasibility using siliceous fuel ash, sourced from thermal power stations Rhenish region Germany, partial replacement mortar formulations. Mortar specimens with FA levels ranging 5 wt% to 30 were prepared and tested. Data collected through standardized laboratory testing mechanical properties (compressive flexural strength), physical characteristics (porosity, sorptivity) microstructural analysis via SEM XRD. results showed that increasing content generally led reductions strength increases porosity sorptivity, due mineralogical composition higher water demand linked porous structure. However, when was used at not exceeding 10 wt%, remained within acceptable limits for construction applications. Additionally, use plasticizing admixtures proved effective mitigating workability issues by reducing water-to-binder ratio. These findings highlight that, despite certain limitations, can be safely effectively low percentages, contributing sustainable production reliance on Portland cement. In addition, contributes reduced CO2 emissions lower costs, cost-efficient solutions.

Язык: Английский

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Experiments and Predictive Modelling on Sustainable Cementitious Mortar with Perforated Fly Ash Cenospheres and Effectively Dispersed Nano Silica

Materials Today Communications, Год журнала: 2025, Номер unknown, С. 113020 - 113020

Опубликована: Июнь 1, 2025

Язык: Английский

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