Effect of Iron Phase on Calcination and Properties of Barium Calcium Sulfoaluminate Cement

In this paper, the effect of iron phase content on the calcination and properties of clinker and barium calcium sulfoaluminate cement was studied. The compressive strength of the samples was tested and combined with an XRD and SEM-EDS analysis, and the microstructure and composition of the barium calcium sulfoaluminate clinker and hydrated samples were characterized. The results showed that the oval-shaped particles were C2S minerals, and the hexagonal plate-shaped or rhombohedral dodecahedral particles were C2.75B1.25A3S¯. The Ba element was mainly distributed in the barium calcium sulfoaluminate region, and some of it was dissolved in C2S; the Fe element was distributed between C2.75B1.25A3S¯ and C2S crystal grains in the form of an iron phase solid solution, which acted as a solvent. When the iron phase composition was C4AF and the iron phase content was 5%, the early hydration and later strength were better, and the compressive strength after curing for 1, 3 and 28 days was 73.2 MPa, 97.9 MPa and 106.9 MPa, respectively. A proper amount of the iron phase can reduce the eutectic point of the sintered mature material system, increase the amount of liquid phase, reduce the viscosity of the liquid phase, effectively accelerate the migration of mineral ions and promote the formation and growth of minerals.

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Effect of Gypsum on Hydration and Hardening Properties of Alite Modified Calcium Sulfoaluminate Cement

Materials ◽

10.3390/ma12193131 ◽

2019 ◽

Vol 12 (19) ◽

pp. 3131 ◽

Cited By ~ 6

Author(s):

Pei Li ◽

Zhiqiang Ma ◽

Zhong Zhang ◽

Xumin Li ◽

Xiaolei Lu ◽

...

Keyword(s):

Compressive Strength ◽

Setting Time ◽

Calcium Sulfoaluminate Cement ◽

Experimental Conditions ◽

Calcium Sulfoaluminate ◽

Ion Doping ◽

Iron Phase ◽

Calcium Sulphoaluminate ◽

Barium Ion ◽

Late Stages

Calcium sulphoaluminate cement (CSA) has the characteristics of quick hardening, high early strength and high impermeability, however its strength growth persistence in the middle and late stages (after the age of 3 days) is poor. In order to improve this disadvantage, the pilot production of alite (C3S) modified CSA (AMCSA) clinker was carried out by liquid phase manipulation and barium ion doping technology. The effects of different dosages of gypsum on the hydration and hardening properties of AMCSA, such as setting time, hydration rate, compressive strength and hydration products, were studied. The results show that the mineral content of ye’elimite, C2S, C3S and iron phase in the calcined AMCSA clinker are 48.5 wt.%, 32.6 wt.%, 11.7 wt.% and 7.2 wt.% respectively, which are close to the designed mineral composition. The stable coexistence of ye’elimite and C3S in the same clinker system is realized. The initial and final setting time of AMCSA are retarded with the increasing gypsum dosage. When the gypsum dosage is 15 wt.% under the experimental conditions in this study, the AMCSA mortar reaches the highest compressive strength at every age. The strength of AMCSA mortar at 28 days is still significantly improved compared with that at 3 days, which indicates that the shortcoming of the low strength growth persistence of CSA in the middle and late stages is improved.

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Properties of Calcium Sulfoaluminate Cement Mortar Modified by Hydroxyethyl Methyl Celluloses with Different Degrees of Substitution

Molecules ◽

10.3390/molecules26082136 ◽

2021 ◽

Vol 26 (8) ◽

pp. 2136

Author(s):

Shaokang Zhang ◽

Ru Wang ◽

Linglin Xu ◽

Andreas Hecker ◽

Horst-Michael Ludwig ◽

...

Keyword(s):

Compressive Strength ◽

Flexural Strength ◽

Bond Strength ◽

Cement Mortar ◽

Retention Rate ◽

Methyl Cellulose ◽

Tensile Bond Strength ◽

Calcium Sulfoaluminate Cement ◽

Calcium Sulfoaluminate ◽

Cement Mortars

This paper studies the influence of hydroxyethyl methyl cellulose (HEMC) on the properties of calcium sulfoaluminate (CSA) cement mortar. In order to explore the applicability of different HEMCs in CSA cement mortars, HEMCs with higher and lower molar substitution (MS)/degree of substitution (DS) and polyacrylamide (PAAm) modification were used. At the same time, two kinds of CSA cements with different contents of ye’elimite were selected. Properties of cement mortar in fresh and hardened states were investigated, including the fluidity, consistency and water-retention rate of fresh mortar and the compressive strength, flexural strength, tensile bond strength and dry shrinkage rate of hardened mortar. The porosity and pore size distribution were also analyzed by mercury intrusion porosimetry (MIP). Results show that HEMCs improve the fresh state properties and tensile bond strength of both types of CSA cement mortars. However, the compressive strength of CSA cement mortars is greatly decreased by the addition of HEMCs, and the flexural strength is decreased slightly. The MIP measurement shows that HEMCs increase the amount of micron-level pores and the porosity. The HEMCs with different MS/DS have different effects on the improvement of tensile bond strength in different CSA cement mortars. PAAm modification can improve the tensile bond strength of HEMC-modified CSA cement mortar.

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The effect of polymer dispersions on the early hydration of calcium sulfoaluminate cement

Journal of Thermal Analysis and Calorimetry ◽

10.1007/s10973-019-08413-3 ◽

2019 ◽

Vol 139 (1) ◽

pp. 319-331

Author(s):

Lin Li ◽

Yu Peng ◽

Ru Wang ◽

Shaokang Zhang

Keyword(s):

Calcium Sulfoaluminate Cement ◽

Early Hydration ◽

Calcium Sulfoaluminate ◽

Polymer Dispersions

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Effect of Steel Slag on Shrinkage Characteristics of Calcium Sulfoaluminate Cement

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1036.263 ◽

2021 ◽

Vol 1036 ◽

pp. 263-276

Author(s):

Hao Ran Huang ◽

Yi Shun Liao ◽

Siraj Ai Qunaynah ◽

Guo Xi Jiang ◽

Da Wei Guo ◽

...

Keyword(s):

Compressive Strength ◽

Relative Humidity ◽

Cement Paste ◽

Steel Slag ◽

Autogenous Shrinkage ◽

Drying Shrinkage ◽

Chemical Shrinkage ◽

Calcium Sulfoaluminate Cement ◽

Calcium Sulfoaluminate ◽

Slag Content

The effects of steel slag with 0, 10%, 20 % and 40% content on the chemical shrinkage, autogenous shrinkage, internal relative humidity, and drying shrinkage of calcium sulfoaluminate cement paste were studied. The results show that the compressive strength of calcium sulfoaluminate cement paste at an early stage decreases gradually when the content of steel slag increases. When the steel slag content is 0 and 10%, the compressive strength of hardened cement pastes gradually decreases at 90 and 180 days, but the samples with steel slag content of 20% and 40% maintain the compressive strength growth within 180 d. With the extension of curing period, the gap of compressive strength is gradually narrowed. The autogenous shrinkage decreases with the increase of steel slag content and has a good linear relationship with the relative humidity inside the paste. The proportion of autogenous shrinkage to chemical shrinkage is deficient, and most chemical shrinkage occurs in the form of the pore volume. Although the trends of drying shrinkage and autogenous are consistent, the former is more severe than the latter.

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Effect of Anhydrite on the Early Hydration Performance of Rapid Setting and Hardening Belite Sulfoaluminate Cement

Materials Science Forum ◽

10.4028/www.scientific.net/msf.898.1990 ◽

2017 ◽

Vol 898 ◽

pp. 1990-1995 ◽

Cited By ~ 1

Author(s):

Ming Zhang Lan ◽

Bin Feng Xiang ◽

Jian Feng Wang ◽

Xu Dong Zhao ◽

Xiao Ying Wang

Keyword(s):

Compressive Strength ◽

Setting Time ◽

High Strength ◽

Cement Clinker ◽

Hydration Kinetics ◽

Early Hydration ◽

Free Lime ◽

Calcium Sulfoaluminate ◽

Setting Times ◽

Rapid Setting

In order to investigate the early hydration behavior of rapid setting and hardening belite sulfoaluminate cements, the methods of X-ray Diffraction, Scanning Electron Microscope, Compressive Strength test and Setting Times test were used to identify and quantify the hydration kinetics and microstructure of this new-found cements in China. The results showed that the main mineral compositions of high belite sulfoaluminate cement clinker included calcium sulfoaluminate (4CaO·3Al2O3·CaSO4), belite (2CaO·SiO2), ferrite phase, free gypsum and free lime. It was found that not only the setting time and compressive strength but also the composition of hydration products were influenced by anhydrite to some extent. Meanwhile, a mass of AFt and AFm generated along with the hydration process at different ages, overlapped, crossed and penetrated through calcium silicate hydrate gel and aluminum oxide to form a relatively dense structure which could contribute to the high strength of cement.

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Properties of calcium sulfoaluminate cement-based grouting materials with LiAl-layered double hydroxides slurries

Advanced Composites Letters ◽

10.1177/2633366x20926522 ◽

2020 ◽

Vol 29 ◽

pp. 2633366X2092652 ◽

Cited By ~ 1

Author(s):

Haiyan Li ◽

Xianping Wang ◽

Xuemao Guan ◽

Dinghua Zou

Keyword(s):

Compressive Strength ◽

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Layered Double Hydroxides ◽

Setting Time ◽

Hydration Products ◽

Calcium Sulfoaluminate Cement ◽

Calcium Sulfoaluminate ◽

Double Hydroxides

In this study, LiAl-layered double hydroxides Lithium aluminum hydrotalcite (LiAl-LDH) with different specific surface area were prepared by the separate nucleation and aging steps (SNAS) method and then were employed to prepare calcium sulfoaluminate cement-based grouting material (CBGM) paste. The influence of LiAl-LDH slurries on fresh and hardened properties of the CBGM paste was investigated in terms of fluidity, stability, setting time, and compressive strength. Additionally, the hydration process and hydration products of the CBGM paste were characterized by hydration heat, X-ray diffraction, differential thermal analysis–thermogravimetry, and Fourier transform infrared analyses. The acquired results illustrated that LiAl-LDH with larger specific surface area led to a faster hydration rate at early age, a lower fluidity, a shorter setting time, and a higher stability. Furthermore, due to the crystal nucleation effect, the addition of LiAl-LDH slurries did not cause a new phase to form but changed the morphology and increased the amount of hydration products, yielding higher compressive strength.

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Using of Different Type Cement in Solidification/Stabilization of MSWI Fly Ash

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.291-294.1870 ◽

2011 ◽

Vol 291-294 ◽

pp. 1870-1874 ◽

Cited By ~ 2

Author(s):

Guo Xia Wei ◽

Han Qiao Liu ◽

Shu Guang Zhang

Keyword(s):

Heavy Metals ◽

Compressive Strength ◽

Fly Ash ◽

Setting Time ◽

Solid Matrix ◽

Cement Type ◽

Calcium Sulfoaluminate Cement ◽

Mswi Fly Ash ◽

Calcium Sulfoaluminate ◽

Aluminate Cement

Solidification tests of MSWI fly ash (FA) with three types of cement including ordinary Portland cements (OPC), calcium sulfoaluminate cement(CSA) and calcium aluminate cement (CAC) were carried out to discuss the effect of cement type on of the FA-cement solid matrix by means of setting time, compressive strength and heavy metals leachability. Results show that the setting time of the FA-cement mixtures using CSA and CAC is shorter than that of OPC. According to compressive strengths demand and the standard of landfill site of municipal solid waste, the dosage of OPC should be limited about 35% by weigh, the dosage of CAC should be limited about 25% by weigh, and the dosage of CSA should be limited more than 40% by weigh.

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Performance and Durability of Rendering and Basecoat Mortars for ETICS with CSA and Portland Cement

Infrastructures ◽

10.3390/infrastructures6040060 ◽

2021 ◽

Vol 6 (4) ◽

pp. 60

Author(s):

Tiago Trigo ◽

Inês Flores-Colen ◽

Luís Silva ◽

Nuno Vieira ◽

Ana Raimundo ◽

...

Keyword(s):

Mechanical Properties ◽

Compressive Strength ◽

Energy Consumption ◽

Portland Cement ◽

Bending Strength ◽

Setting Time ◽

Cement Matrix ◽

Calcium Sulfoaluminate Cement ◽

Calcium Sulfoaluminate ◽

Composite Systems

The production of Portland cement (OP) is commonly associated to significant level of energy consumption and gas emissions. The use of calcium sulfoaluminate cement (CSA) can be a sustainable alternative binder, since its production releases about half of the CO2 emissions and its clinker requires 200 °C lower temperatures, when compared to OP. Furthermore, CSA has fast setting time and achieves higher strength in shorter periods, as well as reduced shrinkage. This paper discusses the incorporation of CSA in rendering mortars and basecoat mortars for ETICS (External Thermal Insulation Composite Systems). The physical-mechanical properties of mortars made with OP and CSA cements were experimental evaluated. The results showed that the introduction of CSA generally improves shrinkage, compressive strength, water absorption at low pressure, enhances the tensile bending strength and decreases the setting time. The amount of CSA introduced into the mixture significantly affected the properties of the cement matrix.

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