Effect of carbonation curing regime on strength and microstructure of Portland cement paste

Chen, Tiefeng; Gao, Xiaojian

doi:10.1016/j.jcou.2019.05.034

Cited by 219 publications

(42 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Peaks related to AFm and AFt phases also vanished with the carbonation curing. Carbonation-induced decomposition of these phases is evident from previous research works [ 48 ]. M- and H-seires samples also showed peaks related to brownmillerite, whose inetnsity also reduced with increased replacement levels of PC.…”

Section: Resultsmentioning

confidence: 67%

“…The OPC samples exhibited comparable compressive strength for all curing regimes, i.e., ambient and carbonation curing regimes. Chen et al [ 48 ] described that carbonation-cured PC-systems show improvement in compressive strengths at early ages while the positive effect weakens with longer age. Other than this, the optimal pre-curing duration before start of carbonation curing, also depends with the carbonation duration; it decreases with the increase in carbonation curing duration [ 48 ].…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

CO2 Uptake and Physicochemical Properties of Carbonation-Cured Ternary Blend Portland Cement–Metakaolin–Limestone Pastes

et al. 2020

View full text Add to dashboard Cite

The feasibility of carbonation curing of ternary blend Portland cement–metakaolin–limestone was investigated. Portland cement was substituted by the combination of metakaolin and limestone at levels of 15%, 30%, and 45% by the mass. The ternary blends were cured with four different combinations of ambient and carbonation curing. The mechanical property, CO2 uptake, and mineralogical variations of the ternary blend pastes were investigated by means of compressive strength test, thermogravimetric analysis, and X-ray diffractometry. In addition, volume of permeable voids and sorptivity of the ternary blends were also presented to provide a fundamental idea of the pore characteristics of the blends. The test results showed that the increasing amount of metakaolin and limestone enhanced the CO2 uptake, reaching 20.7% for the sample with a 45% cement replacement level at 27 d of carbonation. Meanwhile, the compressive strength of the samples was reduced up to 65% upon excessive incorporation of metakaolin and limestone. The samples with a replacement level of 15% exhibited a comparable strength and volume of permeable voids to those of the sample without substitution, proving that the ternary blend Portland cement–metakaolin–limestone can be a viable option toward the development of eco-friendly binders.

show abstract

Section: Resultsmentioning

confidence: 67%

Section: Resultsmentioning

confidence: 99%

CO2 Uptake and Physicochemical Properties of Carbonation-Cured Ternary Blend Portland Cement–Metakaolin–Limestone Pastes

et al. 2020

View full text Add to dashboard Cite

show abstract

“…The compressive strength of CO 2 -cured cement paste increased with curing time within 24 h, and the increment was especially striking in the first 2 h [15]. Carbonation curing leads to a significant improvement in the early strength of cement mortars, but with the extension of the curing age, this positive effect gradually weakens, and excessive carbonation will lead to decalcification of C-S-H and decrease in strength [16]. Therefore, it is very important to choose the proper carbonation curing time.…”

Section: Introductionmentioning

confidence: 96%

“…The mechanism and kinetics of these reactants of carbonation are different. The carbonation mechanism of CH is a direct reaction, but the carbonation mechanism of C-S-H is more complicated [16] (see Equations ( 1) and ( 2)). C 3 S and its hydration product Ca(OH) 2 are the key reactants for early-age carbonation.…”

Section: Introductionmentioning

confidence: 99%

Mechanical and Microstructural Characteristics of Calcium Sulfoaluminate Cement Exposed to Early-Age Carbonation Curing

et al. 2021

View full text Add to dashboard Cite

: The early-age carbonation curing technique is an effective way to improve the performance of cement-based materials and reduce their carbon footprint. This work investigates the early mechanical properties and microstructure of calcium sulfoaluminate (CSA) cement specimens under early-age carbonation curing, considering five factors: briquetting pressure, water–binder (w/b) ratio, starting point of carbonation curing, carbonation curing time, and carbonation curing pressure. The carbonization process and performance enhancement mechanism of CSA cement are analyzed by mercury intrusion porosimetry (MIP), thermogravimetry and derivative thermogravimetry (TG-DTG) analysis, X-ray diffraction (XRD), and scanning electron microscope (SEM). The results show that early-age carbonation curing can accelerate the hardening speed of CSA cement paste, reduce the cumulative porosity of the cement paste, refine the pore diameter distribution, and make the pore diameter distribution more uniform, thus greatly improving the early compressive strength of the paste. The most favorable w/b ratio for the carbonization reaction of CSA cement paste is between 0.15 and 0.2; the most suitable carbonation curing starting time point is 4 h after initial hydration; the carbonation curing pressure should be between 3 and 4 bar; and the most appropriate time for carbonation curing is between 6 and 12 h.

show abstract

“…According to Panesar and Zhang [ 21 ], for lower replacement levels (up to 10%) concrete or mortar with limestone filler has similar properties compared with control mix, but the increase of substitution ratio can affect properties such as strength, porosity and permeability. To mitigate these drawbacks research studies were performed using nano-CaCO 3 [ 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 ]. Ge et al [ 32 ] reported that the addition to mortar/concrete of nano-calcium carbonate (in adequate amounts) increases the compressive strength and reduces average pore diameter.…”

Section: Introductionmentioning

confidence: 99%

CO2 Sequestration in the Production of Portland Cement Mortars with Calcium Carbonate Additions

et al. 2021

View full text Add to dashboard Cite

The paper presents the obtention and characterization of Portland cement mortars with limestone filler and nano-calcite additions. The nano-calcite was obtained by the injection of CO2 in a nano-Ca(OH)2 suspension. The resulted nano-CaCO3 presents different morphologies, i.e., polyhedral and needle like crystals, depending on the initial Ca(OH)2 concentration of the suspension. The formation of calcium carbonate in suspensions was confirmed by X-ray diffraction (XRD), complex thermal analysis (DTA-TG), scanning electron microscopy (SEM) and transmission electron microscopy (TEM and HRTEM). This demonstrates the viability of this method to successfully sequestrate CO2 in cement-based materials. The use of this type of nano-CaCO3 in mortar formulations based on PC does not adversely modify the initial and final setting time of cements; for all studied pastes, the setting time decreases with increase of calcium carbonate content (irrespective of the particle size). Specific hydrated phases formed by Portland cement hydration were observed in all mortars, with limestone filler additions or nano-CaCO3, irrespective of curing time. The hardened mortars with calcium carbonate additions (in adequate amounts) can reach the same mechanical strengths as reference (Portland cement mortar). The addition of nano-CaCO3 in the raw mix increases the mechanical strengths, especially at shorter hardening periods (3 days).

show abstract

Effect of carbonation curing regime on strength and microstructure of Portland cement paste

Cited by 219 publications

References 49 publications

CO2 Uptake and Physicochemical Properties of Carbonation-Cured Ternary Blend Portland Cement–Metakaolin–Limestone Pastes

CO2 Uptake and Physicochemical Properties of Carbonation-Cured Ternary Blend Portland Cement–Metakaolin–Limestone Pastes

Mechanical and Microstructural Characteristics of Calcium Sulfoaluminate Cement Exposed to Early-Age Carbonation Curing

CO2 Sequestration in the Production of Portland Cement Mortars with Calcium Carbonate Additions

Contact Info

Product

Resources

About