Carbonation of alkali activated binders and comparison with the performance of ordinary Portland cement and blended cement binders

Charitha, V.; Athira, G.; Bahurudeen, A.; Shekhar, Shivang

doi:10.1016/j.jobe.2022.104513

Cited by 12 publications

(6 citation statements)

References 127 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…5, respectively. The first peak on the DTG curves from 30°C to 200°C is associated with the structurally unbound water and dehydration of C-A-S-H gels in all three mixes [15,16]. The peaks are less pronounced in the samples exposed for 7 days than in samples exposed for 28 days, which can be attributed to the longer decalcification time of the C-A-S-H and formation of more CaCO3.…”

Section: Thermogravimetric Analysismentioning

confidence: 93%

“…5). The lowest carbonation resistance of S3 after 28 days, despite the highest Ms, could be explained by insufficient amount of alkali in the mix and less formation of CO2 -absorbing hydrotalcite [3,14,15]. The hydrotalcite phases are less emphasised after 7 and 28 days of exposure due to conversion of hydrotalcite to CaCO3.…”

Section: Thermogravimetric Analysismentioning

confidence: 96%

“…In addition, the ability of hydrotalcite to absorb CO2 may increase carbonation resistance [3,14]. It has been reported that slag activation with higher alkali dosage results in formation of more hydrotalcite-like phases, which can absorb more CO2 [3,14,15]. However, when the alkali dosage is too high (e.g., 10%), not all Na2O contributes to the activation reaction and may increase the carbonation depth due to carbonationinduced cracking [15].…”

Section: Introductionmentioning

confidence: 99%

“…It has been reported that slag activation with higher alkali dosage results in formation of more hydrotalcite-like phases, which can absorb more CO2 [3,14,15]. However, when the alkali dosage is too high (e.g., 10%), not all Na2O contributes to the activation reaction and may increase the carbonation depth due to carbonationinduced cracking [15]. This paper presents the results of the analysis of the microstructural changes of three alkali-activated slag concrete mixes with different alkali content and silica modulus after exposure to accelerated carbonation.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Influence of alkali content and silica modulus on the carbonation kinetics of alkali-activated slag concrete

Olivera

Serdar

2022

MATEC Web Conf.

View full text Add to dashboard Cite

Carbonation is inevitable process during the service life of concrete structures, where CO2 causes decalcification of the calcium-bearing phases. These changes affect the durability of concrete and accelerate the corrosion of reinforcement. Alkali-activated materials (AAMs) are alternative, cement-free binders based on aluminosilicate rich precursor and alkaline activator. The interest in AAMs increased during the last century, due to the production process with low CO2 footprint comparing to Portland cement (PC) concrete, the possibility to use wide range of industrial by-products as precursors and comparable performance to PC concrete. Despite the extensive research in this field, the carbonation resistance of AAMs needs to be better understood, due to the differences and complexity of binder chemistry compared to PC concrete. The propagation of carbonation process will depend on chemical composition of the precursors and the type and dosage of activators. This paper presents the results of microstructural changes of three alkali-activated concrete mixes after exposure to accelerated carbonation. Ground granulated blast furnace slag was used as a precursor and sodium hydroxide and sodium silicate as activators. Three mixes have constant water to binder ratio and slag content, while alkali content and silica modulus were varied. The carbonation resistance was evaluated by testing carbonation depth after 7 and 28 days of exposure in carbonation chamber. Microstructural changes during carbonation were investigated by thermogravimetric analysis and mercury intrusion porosimetry.

show abstract

Section: Thermogravimetric Analysismentioning

confidence: 93%

Section: Thermogravimetric Analysismentioning

confidence: 96%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Influence of alkali content and silica modulus on the carbonation kinetics of alkali-activated slag concrete

Olivera

Serdar

2022

MATEC Web Conf.

View full text Add to dashboard Cite

show abstract

“…1) [54][55][56][57] . However, raw CCRs are not applicable in construction due to their reactivity 58 , strong basicity and low plasticity. Moreover, a tendency to consume carbon dioxide from air 59 requires immediate use of CCR after isolation, blocking the possibility of storing CCR without chemical modification for a long time 60 .…”

Section: Sustainable Application Of Calcium Carbide Residue As a Fill...mentioning

confidence: 99%

Sustainable application of calcium carbide residue as a filler for 3D printing materials

Samoylenko

Rodygin

Ananikov

2023

Sci Rep

View full text Add to dashboard Cite

Industrial activity results in ton-scale production of calcium carbide and generation of a significant amount of calcium carbide residue (CCR), which is often disposed of in the environment as waste. CCR is an active chemical, and rain washes away alkali from sludge, changing the pH of soils and water and damaging the environment. In this work, we explored new opportunities for the utilization of CCR in view of the coming industrial uptake of digital design and additive technologies. Amazingly, CCR can be successfully used as a filler for the modification of 3D printed materials towards the introduction of hybrid organic/inorganic frameworks. A series of commercially available plastics (PLA, ABS, Nylon, PETG, SBS) were successfully used as matrices for CCR-based composite production with high CCR contents up to 28%. Tensile analyses showed increases in tensile strength and Young’s modulus of 9% and 60%, respectively. Moreover, in comparison with the pure plastics, the CCR-based materials better maintained the digitally designed shape (lower shrinkage). Importantly, CCR-filled materials are 3D printable, making them very promising components in the building sector. Considering the amount of already available CCR stored in the environment, this material is available in large quantities in the near future for hybrid materials, and anticipated opportunities exist in the additive manufacturing sector. The involvement of CCR in practical composite materials is equally important for environmental protection and reuse of already available multiple-ton wastes.

show abstract

Carbonation of Concretes with Different Binder Chemistry – A Comparative Analysis

et al. 2023

View full text Add to dashboard Cite

Carbonation of alkali activated binders and comparison with the performance of ordinary Portland cement and blended cement binders

Cited by 12 publications

References 127 publications

Influence of alkali content and silica modulus on the carbonation kinetics of alkali-activated slag concrete

Influence of alkali content and silica modulus on the carbonation kinetics of alkali-activated slag concrete

Sustainable application of calcium carbide residue as a filler for 3D printing materials

Carbonation of Concretes with Different Binder Chemistry – A Comparative Analysis

Contact Info

Product

Resources

About