Accelerated carbonation as a fast curing technology for concrete blocks

Shi, Caijun; Tu, Zhenjun; Guo, Ming-Zhi; Wang, Dehui

doi:10.1016/b978-0-08-102001-2.00015-2

Cited by 16 publications

(6 citation statements)

References 130 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The appearance of Q 1 and Q 2 groups clearly indicates the hydration process in C 3 S samples. ,, Meanwhile, the presence of Q 3 and Q 4 groups reflects the formation of an amorphous silica gel formed by the decomposition of the calcium silicate hydrate along with the formation of CaCO 3 . ,,− This assumption is underlined by complementary FTIR measurements (Supporting Information Figure S1) that proved the presence of CaCO 3 moieties as calcite (1471, 875, and 712 cm –1 ) and aragonite (1465, 854, and 700 cm –1 ) . The intensity of these lines increases upon hydration time which suggests the formation of CaCO 3 moieties during the hydration, revealing the carbonation of hydrated C 3 S. , The carbonation of the surface of C 3 S particles in the presence of water is based on the chemical reaction () leading to the formation of CaCO 3 and silica gel …”

Section: Resultsmentioning

confidence: 88%

“…Despite the extensive everyday application of concrete and its ubiquitous presence in everyday life, its chemistry, leading to formation of complex nanocrystalline structures, is still not completely understood . Recently, because of strict worldwide regulations on greenhouse gas emissions, it was suggested to capture CO 2 during the industrial production of building elements from concrete. , This stimulates further research into the relations between the macroscopic properties of concrete and the microscopic chemical processes taking place, for example, hydration, carbonation, and so on, which lead to the formation of complex nanoscale structures inside the concrete.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Direct Observation of Carbonate Formation in Partly Hydrated Tricalcium Silicate by Dynamic Nuclear Polarization Enhanced NMR Spectroscopy

et al. 2021

View full text Add to dashboard Cite

Solid-state NMR combined with dynamic nuclear polarization (DNP NMR) is used to study hydration processes in tricalcium silicate (Ca3SiO5, abbreviated as C3S) samples. The studied C3S samples have experienced early stage hydration (1–30 h) and slow aging (9 years) processes. The appearance of Q3 and Q4 lines in the 29Si MAS and 1H → 29Si CP MAS NMR spectra obtained for partly hydrated C3S samples indicated the formation of amorphous silica which corresponds to their carbonation, which was corroborated by complementary FTIR data. Significant DNP signal enhancements obtained for the studied samples allowed to further investigate the C3S carbonation process in detail employing the 1H → 29Si CP MAS FSLG HETCOR technique. Finally, DNP enhanced 1H → 13C CP MAS and 1H → 13C CP MAS FSLG HETCOR techniques enabled to directly observe the formation of carbonate moieties in partly hydrated C3S samples.

show abstract

Section: Resultsmentioning

confidence: 88%

Section: Introductionmentioning

confidence: 99%

Direct Observation of Carbonate Formation in Partly Hydrated Tricalcium Silicate by Dynamic Nuclear Polarization Enhanced NMR Spectroscopy

et al. 2021

View full text Add to dashboard Cite

show abstract

“…One important factor is CaO content. Shi et al [29] describe how, regardless of cement type, the theoretical maximum CO 2 concentration increases with CaO content-1.0 tonnes of cement could consume 0.5 tonnes of CO 2 . The authors also highlighted the specific raw materials used, water-to-cement ratio, sand-to-cement ratio, compaction pressure, preconditioning before accelerated carbonation, effects of both concentration and pressure of CO 2 , and further curing after accelerated carbonation as other important factors.…”

Section: Accelerated Carbonation Curing Of Concretementioning

confidence: 99%

Toward Carbon-Neutral Concrete through Biochar–Cement–Calcium Carbonate Composites: A Critical Review

2022

View full text Add to dashboard Cite

High-density, high-permanence forms of carbon storage are in demand to save storage space on land or at sea while allowing the world to reach its climate targets. Biochar and calcium carbonate are two such forms that have been considered largely separately in the literature for carbon storage. In this paper, we consider how biochar and calcium carbonate might interact when they are used together with cement as part of a carbon storage system, ideally to form a carbon-neutral concrete. The carbon storage system stores atmospherically absorbed CO2 within concrete, thereby reducing carbon in the atmosphere. In addition, such a system will help in reducing cement usage, thus reducing the need for clinker in cement manufacturing and directly reducing CO2 emissions that result from limestone calcination during clinker manufacturing. Another benefit of such a composite storage system is its use in building structures, a use that has positive environmental and social impact. Thus, further research on the properties of this composite material is warranted. This paper explores the literature on the use of biochar combined with calcium carbonate and cement as carbon storage material. The use of recycled carbon aggregates (RCAs) and LC3 concrete as part of this approach is reviewed. The paper also addresses the possible compressive strength range of the biochar–cement–calcium carbonate composite material, along with other performance expectations. Obstacles to scaling the use of carbon-neutral concrete are identified and an array of research directions are presented, with the goal of improving carbon-neutral concrete and its use.

show abstract

“…Nonetheless, carbonation reduces the pH value of the concrete, destroying the passivity of the reinforcement's protective layer. Anyway, it takes a few years for weathering carbonation to reach the level of reinforcement, whereas rapid carbonation could be used on unreinforced/plain concrete to eliminate the risk of reinforcement corrosion in concrete [66] [67].…”

Section: Water Permeabilitymentioning

confidence: 99%

Study on Coarse Recycled Concrete Aggregate

Singh¹,

Nayak²,

Kumar³

et al. 2022

cea

View full text Add to dashboard Cite

The use of recycled concrete aggregate (RCA) is one of the best solutions to mitigate the problem of ecological instability created by concrete waste. RCA has less crushing strength, impact resistance, specific gravity, and more water absorption capacity than the natural aggregate (NA). To overcome the compromised properties of RCA, a comprehensive study supported by the experimental investigation is required. This paper prescribes a methodology based on experimental investigation for the use of coarse-RCA (C-RCA) of size (4.75-20mm) as 100% replacement of coarse-NA in fresh concrete. A "remodified two-stage mixing approach (R-TSMA)" supported by a physical treatment method is proposed here to increase the bond strength between RCA and new mortar. Micro-structure of RCA-C has been studied via optical microscope as well as Scanning Electron Microscope (SEM). Effect of parent concrete quality is influential only at early curing age (7 and 14 days), but after 28 days of curing its influence reduced, such that RCA-C sample showed 5% higher compressive strength and about 4% higher in flexural strength than NA-C. At 90 days of curing, all RCA samples showed higher compressive and flexural strength than NA-C. Similarly, carbonation curing enhanced the strength of RCA-C by higher margin than NA-C.

show abstract

Accelerated carbonation as a fast curing technology for concrete blocks

Cited by 16 publications

References 130 publications

Direct Observation of Carbonate Formation in Partly Hydrated Tricalcium Silicate by Dynamic Nuclear Polarization Enhanced NMR Spectroscopy

Direct Observation of Carbonate Formation in Partly Hydrated Tricalcium Silicate by Dynamic Nuclear Polarization Enhanced NMR Spectroscopy

Toward Carbon-Neutral Concrete through Biochar–Cement–Calcium Carbonate Composites: A Critical Review

Study on Coarse Recycled Concrete Aggregate

Contact Info

Product

Resources

About