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Showing 1 to 15 of 15 for “"pozzolanic reaction"”.
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Biomass and Coal Fly Ash in Concrete: Strength, Durability, Microstructure, Quantitative Kinetics of Pozzolanic Reaction and Alkali Silica Reaction Investigations.
… to that of traditional (neat) coal fly ash. Pozzolanic reactions occur simultaneously but not necessarily proportionally to strength development. Mixtures of biomass and coal fly ash in all proportions mitigate alkali-silica-reaction-based (ASR-based) expansion in concrete. Biomass-specific …
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Estabilização de areia com adição de cal e cinza volante
… coal - and lime, when wetted, presents a pozzolanic reaction and cements the sand grains. It was intended to confirm research work made abroad, by using a fly ash produced in a thermo-electric plant from the southern part of Brazil. It was taken into account the possibilities that this …
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Assessment of lime-treated clays under different environmental conditions
… namely cation exchange, flocculation and pozzolanic reaction, which cause the changes in the soil characteristics after adding lime in the presence of water. The dispute is about whether these mechanisms occur in a sequential or synchronous manner. More precisely, the controversy concerns …
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Estabilização de areia com cinza volante e cal; efeito do cimento como aditivo e de brita na mistura
… cementation of sand grains by the product from pozzolanic reaction of lime with fly ash in wet condition. Three different mixtures were studied. First mixture: lime 4%, fly ash 13%, sand 83%, considered the basic one. Second mixture: same with 1% portland cement of high early strength to study …
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Characterization of pozzolanic cement for radioactive waste disposal
… analyze the chemical and physical properties of pozzolanic cement. The principle objective of this research was to determine whether pozzolanic cement is a suitable material for permanently encasing high-level radioactive waste (HLW) and spent-nuclear fuel (SNF) in disposal canisters. This …
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Mitigating alkali silica reaction in recycled concrete
… aggregate (RCA) that had shown alkali silica reaction (ASR) distress was evaluated. It was found that ASR mitigation was needed to prevent continued expansion. Several mitigation methods were evaluated and compared to conventional concrete using the testing procedures of ASTM C 1260/1567 and …
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Nanoindentation characterization of clay minerals and clay-based hybrid bio-geomaterials
… Thus, this study proposes that slow and weak pozzolanic reaction between clay and lime produces cementitious binder network consisting of C-S-H phase. Interaction of the biopolymer (sticky rice) with clay and C-S-H resulted in intercalated nanocomposites that have superior mechanical and …
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Development of low-clinker concrete: partial replacement of cement with calcined clay and limestone, based on selected African raw materials
… minerals present in the clay, the filler effect, pozzolanic reaction, formation of carboaluminate phases, stabilisation of the ettringite phase, and the internal surface area of the clay.
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The influence of curing techniques and chemical admixtures on the properties of concrete
… to permit the continuation of the hydration or pozzolanic reaction. The objective of curing is to ensure the progress of hydration reactions causing the filling and discontinuity of capillary voids by hydrated compounds in newly placed concrete. Modern curing methods are generally classified as …
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Soft Soil Stabilisation Using a Novel Blended Cementitious Binder Produced From Waste Fly Ashes
… of FGD gypsum has been observed to enhance the pozzolanic reaction, leading to improved geotechnical properties; mainly UCS which increased over time of curing and exceeded that for the soil treated with reference cement, after 180 days. The results obtained from XRD analysis, SEM testing and …
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The nanostructure and degradation of C-S-H in Portland and blended cements
… spaces and additional C-S-H resulted from the pozzolanic reaction. The chemical composition of C-S-H could not be determined by SEM-EDX because of intermixing with other phases; TEM-EDX was necessary. Inner product C-S-H morphology was fine and homogeneous and that of outer product C-S-H was …
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The Influence of Amorphous, Sub-Micrometer Silica Particles in Cement Pastes and Mortars with Very Low Water-to-Cement Ratios (Ultra-High Performance Concrete)
… hydration due to its dissolution and subsequent pozzolanic reaction to calcium–silicate–hydrate phases (C–S–H phases) and/or due to a heterogeneous nucleation of C–S–H phases from alite hydration on silica surfaces (seeding effect). Herein, the influence of the reactivity of silica has been …
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Self-healing strain-hardening cementitious composites (SH2CC) for cyclic loading environments
… mechanical recovery through hydration and pozzolanic reaction with water supply, and more prominently accelerate crack sealing through enhanced carbonation at crack tips. TEA addition was able to pause the initial hydration/carbonation process of SH2CC under air curing, thus resuming the …
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Valorisation of wind turbine blades into concrete : a contribution towards a more sustainable approach
… (due to the retardant properties of wood and the pozzolanic reaction occurring at the later ages), followed by the increase in compressive strength after 90 days (reaching between 87% and 96% of reference mix strength). The use of CFFT technology resulted in a 90-100% increase in compressive …
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Durability of cement and concrete matrices incorporating nanocellulose fibers (NCF)
L'introduction des nanofibres de cellulose (NFC) représente une avancée significative dans le domaine des matériaux de construction, offrant des propriétés mécaniques, une durabilité et une rentabilité supérieures par rapport aux fibres traditionnelles. Face aux inquiétudes concernant la durabilité …