Evolution of elastic behavior of alite paste at early hydration stages

Huang, Hai; Yuan, Qiang; Zuo, Shenghao; Shi, Caijun

doi:10.1111/jace.17354

Cited by 22 publications

(12 citation statements)

References 57 publications

(128 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Finally, the storage modulus of the mixture demonstrates a continuous increase concurrent with the enlargement of the C–S–H bridges 9,25 . Additionally, recent studies also found that a liner relation between the formation of C–S–H and the increase of storage modulus 27 …”

Section: Resultsmentioning

confidence: 77%

Early structural build‐up behavior, setting mechanism, and nanostructure of alkali‐activated GGBFS mixtures

Dai,

Aydin,

Yardimci

et al. 2023

J Am Ceram Soc.

View full text Add to dashboard Cite

The initial changes in the microstructure of alkali‐activated slag cement (AAS) characterize the rheological behavior, initial structuration, and setting times of the mixture. In this study, the relationships among the rheological behavior, solidification process, and nanostructure changes of sodium hydroxide‐activated slag (NH–AAS) and sodium silicate‐activated slag (SS–AAS) pastes over time are investigated by small amplitude oscillation shear test, isothermal calorimetry, scanning electron microscopy analyses, and 1H–29Si cross‐polarization magic‐angle spinning nuclear magnetic resonance spectroscopy (CP MAS NMR) and 29Si MAS NMR spectroscopy. Test results showed that the NH–AAS reaches its initial setting time following a continuously proceeding structuration process, whereas the SS–AAS reaches its initial setting with an abrupt increase in the structuration process. At their initial setting times, the NH–AAS and SS–AAS mixtures release similar heat and reach a similar reaction degree. The SS–AAS mixture had more N–A–S–H formation than C–A–S–H at the initial setting time. On the other hand, the amount of C–A–S–H was similar to N–A–S–H in the NH–AAS mixture. The gradual N–A–S–H gel degradation to form C–A–S–H was observed during the acceleration period for the SS–AAS mixture.

show abstract

Section: Resultsmentioning

confidence: 77%

Early structural build‐up behavior, setting mechanism, and nanostructure of alkali‐activated GGBFS mixtures

Dai,

Aydin,

Yardimci

et al. 2023

J Am Ceram Soc.

View full text Add to dashboard Cite

show abstract

“…28 On the other hand, the G′ of the C 3 S paste increases continuously with time due to the dissolution−precipitation reaction upon contact with water. 51 In the very beginning, the G′ of the paste is linked mainly with the high ion concentration in the pore solution due to the massive dissolution of C 3 S (initial low C−S−H precipitation), resulting in a very cohesive behavior at rest but fragile once sheared (γ ≥ γ cr ). Following the hydration process, the continuous C−S−H particles' precipitation starts to influence the overall contact area, which increases over time (contact aging 61 ) until C−S−H percolation and final rigidification of the paste (setting).…”

Section: ■ Results and Discussionmentioning

confidence: 99%

“…On the other hand, the G ′ of the C 3 S paste increases continuously with time due to the dissolution–precipitation reaction upon contact with water . In the very beginning, the G ′ of the paste is linked mainly with the high ion concentration in the pore solution due to the massive dissolution of C 3 S (initial low C–S–H precipitation), resulting in a very cohesive behavior at rest but fragile once sheared (γ ≥ γ cr ).…”

Section: Resultsmentioning

confidence: 99%

“…The elastic regime is defined via an amplitude sweep (AS) measurement, in which a range of strain amplitudes (γ = 10 –3 –10 2 %) is imposed and the elastic ( G ′) and viscous ( G ″) moduli are measured. , The end of elasticity ( G cr ′ , γ cr ) is defined as the point in which the value of G ′ is reduced by 10–20% from its maximum values in the elastic plateau G lin ′ . For γ < γ cr , the range of strain deformation for which we observe a linear behavior is determined.…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Detecting Early-Stage Cohesion Due to Calcium Silicate Hydration with Rheology and Surface Force Apparatus

Liberto

Nenning

Bellotto³

et al. 2022

Langmuir

View full text Add to dashboard Cite

Extremely robust cohesion triggered by calcium silicate hydrate (C−S−H) precipitation during cement hardening makes concrete one of the most commonly used man-made materials. Here, in this proof-of-concept study, we seek an additional nanoscale understanding of early-stage cohesive forces acting between hydrating model tricalcium silicate (C 3 S) surfaces by combining rheological and surface force measurements. We first used time-resolved small oscillatory rheology measurements (SAOSs) to characterize the early-stage evolution of the cohesive properties of a C 3 S paste and a C−S−H gel. SAOS revealed the reactive and viscoelastic nature of C 3 S pastes, in contrast with the nonreactive but still viscoelastic nature of the C−S−H gel, which proves a temporal variation in the cohesion during microstructural physicochemical rearrangements in the C 3 S paste. We further prepared thin films of C 3 S by plasma laser deposition (PLD) and demonstrated that these films are suitable for force measurements in the surface force apparatus (SFA). We measured surface forces acting between two thin C 3 S films exposed to water and subsequent in situ calcium silicate hydrate precipitation. With the SFA and SFA-coupled interferometric measurements, we resolved that C 3 S surface reprecipitation in water was associated with both increasing film thickness and progressively stronger adhesion (pull-off force). The lasting adhesion developing between the growing surfaces depended on the applied load, pull-off rate, and time in contact. These properties indicated the viscoelastic character of the soft, gel-like reprecipitated layer, pointing to the formation of C− S−H. Our findings confirm the strong cohesive properties of hydrated calcium silicate surfaces that, based on our preliminary SFA measurements, are attributed to sharp changes in the surface microstructure. In contact with water, the brittle and rough C 3 S surfaces with little contact area weather into soft, gel-like C−S−H nanoparticles with a much larger surface area available for forming direct contacts between interacting surfaces.

show abstract

“…The small-amplitude oscillatory shear is commonly used to test the viscoelasticity of pastes, and the applied shear rate varies with time in the form of a sinusoidal function. 47 However, as the shear rate of cement pastes generally increases linearly or logarithmically in most tests (Figure 3A), the rheological parameters are usually measured using a rotational coaxial cylinder.…”

Section: Selection Of Rheological Testing Schemementioning

confidence: 99%

Method for calculating dynamic yield stress of fresh cement pastes using a coaxial cylinder system

Peng

Unluer

et al. 2021

J. Am. Ceram. Soc.

View full text Add to dashboard Cite

Fresh cement mixes are multiscale, multiphase, solid-liquid dispersion systems. 1 The individual particles in these mixes undergo irregular Brownian motion, collisions, and friction, and they exhibit electrostatic repulsion and Van der Waals forces. [2][3][4] In terms of rheological properties, cement paste shows more plastic properties when it is fresh. With continuous hydration, the cement paste gradually loses its fluidity, sets, and hardens into a semisolid or solid-phase system dominated by viscoelasticity. [5][6] The rheological properties strongly influence the macroscopic working performance of fresh cement-based materials. This performance can be characterized by specific rheological models that represent a functional relationship (i.e., a constitutive equation) between the shear stress and the shear rate of the flowing material. 7 For example, in the commonly used Bingham model, the two basic rheological parameters are the yield stress and plastic viscosity. [8][9] Meanwhile, the rheological properties reflect the change in the viscosity of the cement paste with variations in the external shear force. When the first derivative value of the shear

show abstract

Evolution of elastic behavior of alite paste at early hydration stages

Cited by 22 publications

References 57 publications

Early structural build‐up behavior, setting mechanism, and nanostructure of alkali‐activated GGBFS mixtures

Early structural build‐up behavior, setting mechanism, and nanostructure of alkali‐activated GGBFS mixtures

Detecting Early-Stage Cohesion Due to Calcium Silicate Hydration with Rheology and Surface Force Apparatus

Method for calculating dynamic yield stress of fresh cement pastes using a coaxial cylinder system

Contact Info

Product

Resources

About