Rheological behavior of calcium sulfoaluminate cement paste with supplementary cementitious materials

Compared to ordinary Portland cement (OPC), calcium sulfoaluminate cement (CSA) displays very early-age strength and faster heat-releasing rate during hydration. In the present paper, the early hydration heat of CSA paste with influences of supplementary cementitious materials (SCMs) and water to cement (or binder) ratio (w/c) is systematically studied by measuring the heat-releasing rate using a calorimeter. Three traditional SCMs—silica fume (SF), fly ash (FA) and ground granulated blast furnace slag (SL)—were used in the study. A water to cement or binder ratio (w/c) between 0.19 and 0.73 was used in the mixtures. The results show that three exothermic peaks were presented during hydration—dissolution exothermic peak and two reaction exothermic peaks. With the w/c of 0.3, the first and second reaction peaks of the CSA paste are as high as 17.8 times and 4.1 times that of OPC paste, and the occurring time is much earlier than that of the OPC paste. The second reaction peak appears earlier, and the third reaction peak appears later in the pastes with addition of SF than in those without SF. Decreasing w/c can greatly reduce the two reaction peaks of the paste, and it looks that there is a critical value of w/c between 0.24 and 0.30. Above the critical value, the effect of w/c is minor, and below that the influence is obvious. An optimal use of SCMs in CSA pastes under different w/c can greatly decrease the heat releasing while maintaining the required strength.

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The effect of supplementary cementitious materials on chloride binding in hardened cement paste

Cement and Concrete Research ◽

10.1016/j.cemconres.2011.01.001 ◽

2012 ◽

Vol 42 (1) ◽

pp. 1-7 ◽

Cited By ~ 213

Author(s):

M.D.A. Thomas ◽

R.D. Hooton ◽

A. Scott ◽

H. Zibara

Keyword(s):

Cement Paste ◽

Cementitious Materials ◽

Supplementary Cementitious Materials ◽

Hardened Cement ◽

Chloride Binding ◽

Hardened Cement Paste

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Use of Algerian Natural Mineral Deposit as Supplementary Cementitious Materials

International Journal of Engineering Research in Africa ◽

10.4028/www.scientific.net/jera.34.48 ◽

2018 ◽

Vol 34 ◽

pp. 48-58 ◽

Cited By ~ 1

Author(s):

Karima Arroudj ◽

Saida Dorbani ◽

Mohamed Nadjib Oudjit ◽

Arezki Tagnit-Hamou

Keyword(s):

Mechanical Strength ◽

Calcium Hydroxide ◽

Cement Paste ◽

Cementitious Materials ◽

Pozzolanic Reaction ◽

Heat Of Hydration ◽

Cement Industry ◽

Supplementary Cementitious Materials ◽

Natural Mineral ◽

Different Ages

Much of the current research on concrete engineering has been focused on including siliceous additions as supplementary cementitious materials (SCMs). Silica reacts with Calcium hydroxide release during cement hydration, and produces more C-S-H. The latter contributes to increase compactness, mechanical strengths and sustainability of concrete. This paper explores the hydration characteristics of cement paste based on various natural mineral additions, that are very abundant in Algeria and present a high silica content (ground natural pozzolana “PZ” and ground dune sand “DS”). For this purpose, several analyses were carried out on modified cement pastes and mortars. TheseSCMswere introduced by replacement levels of 15, 20 and 25 by weight of cement. We first, studied the effect of these SCMs on the heat of hydration and mechanical strength of mortars at different ages. The evolution of hydration of modified paste was studied, by using Thermal analysis (TG/TDA) at different ages, to analyze the Calcium Hydroxide (CH) content of the modified pastes. It is shown that the CH content of the mixes including SCMs is lower than that of the plain cement paste, indicating that silica reacts with the cement paste through a pozzolanic reaction. Increased pozzolanic activity results in higher amounts of Calcium Silicate Hydrate in the paste, which in turn results in higher compressive strength for modified cement mortars. Due to its crystalline morphology, the ground DS particles present a partial pozzolanic effect, compared to PZ which is semi-crystalline. Modified mortars by 20% DS can be the optimal composition. It presents satisfactory results: good mechanical strength and low heat of hydration. It can lead to an economic and sustainable concrete. Ground DS is very abounded in Africa and free of any impurities and can be a good alternativeSCMsin cement industry.

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Hydration Characteristics of Cement Paste Containing Supplementary Cementitious Materials

Arabian Journal for Science and Engineering ◽

10.1007/s13369-012-0193-6 ◽

2012 ◽

Vol 37 (3) ◽

pp. 535-544 ◽

Cited By ~ 7

Author(s):

A. Elahi ◽

Q. U. Z. Khan ◽

S. A. Barbhuiya ◽

P. A. M. Basheer ◽

M. I. Russell

Keyword(s):

Cement Paste ◽

Cementitious Materials ◽

Supplementary Cementitious Materials ◽

Hydration Characteristics

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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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The damage of calcium sulfoaluminate cement paste partially immersed in MgSO4 solution

Materials and Structures ◽

10.1617/s11527-015-0532-7 ◽

2015 ◽

Vol 49 (1-2) ◽

pp. 719-727 ◽

Cited By ~ 8

Author(s):

Zanqun Liu ◽

Xiangning Li ◽

Dehua Deng ◽

Geert De Schutter

Keyword(s):

Cement Paste ◽

Calcium Sulfoaluminate Cement ◽

Calcium Sulfoaluminate

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The Influence of Chemical Activators on the Hydration Behavior and Technical Properties of Calcium Sulfoaluminate Cements Blended with Ground Granulated Blast Furnace Slags

Buildings ◽

10.3390/buildings11070268 ◽

2021 ◽

Vol 11 (7) ◽

pp. 268

Author(s):

Milena Marroccoli ◽

Antonio Telesca

Keyword(s):

Blast Furnace ◽

Co2 Emissions ◽

Cementitious Materials ◽

Supplementary Cementitious Materials ◽

X Ray Diffraction ◽

Cement Production ◽

Blended Cements ◽

Calcium Sulfoaluminate ◽

Technical Performance ◽

Technical Properties

The manufacture of Ordinary Portland cement (OPC) generates around 8% of the global CO2 emissions related to human activities. The last 20 years have seen considerable efforts in the research and development of methods to lower the carbon footprint associated with cement production. Specific focus has been on limiting the use of OPC and employing alternative binders, such as calcium sulfoaluminate (CSA) cements, namely special hydraulic binders obtained from non-Portland clinkers. CSA cements could be considered a valuable OPC alternative thanks to their distinctive composition and technical performance and the reduced environmental impact of their manufacturing process. To additionally reduce CO2 emissions, CSA cements can also be blended with supplementary cementitious materials. This paper investigates the influence of two separately added chemical activators (NaOH or Na2CO3) on the technical properties and hydration behavior of four CSA blended cements obtained by adding to a plain CSA cement two different ground granulated blast furnace slags. Differential thermal-thermogravimetric, X-ray diffraction and mercury intrusion porosimetry analyses were done, along with shrinkage/expansion and compressive strength measurements.

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Hydration–Strength–Workability–Durability of Binary, Ternary, and Quaternary Composite Pastes

Materials ◽

10.3390/ma15010204 ◽

2021 ◽

Vol 15 (1) ◽

pp. 204

Author(s):

Yi Han ◽

Seokhoon Oh ◽

Xiao-Yong Wang ◽

Run-Sheng Lin

Keyword(s):

Compressive Strength ◽

Cement Paste ◽

Carbon Emissions ◽

Cementitious Materials ◽

Heat Of Hydration ◽

Surface Resistivity ◽

Cement Industry ◽

Supplementary Cementitious Materials ◽

Limestone Powder ◽

Alternative Materials

At present, reducing carbon emissions is an urgent problem that needs to be solved in the cement industry. This study used three mineral admixtures materials: limestone powder (0–10%), metakaolin (0–15%), and fly ash (0–30%). Binary, ternary, and quaternary pastes were prepared, and the specimens’ workability, compressive strength, ultrasonic pulse speed, surface resistivity, and the heat of hydration were studied; X-ray diffraction and attenuated total reflection Fourier transform infrared tests were conducted. In addition, the influence of supplementary cementitious materials on the compressive strength and durability of the blended paste and the sustainable development of the quaternary-blended paste was analyzed. The experimental results are summarized as follows: (1) metakaolin can reduce the workability of cement paste; (2) the addition of alternative materials can promote cement hydration and help improve long-term compressive strength; (3) surface resistivity tests show that adding alternative materials can increase the value of surface resistivity; (4) the quaternary-blended paste can greatly reduce the accumulated heat of hydration; (5) increasing the amount of supplementary cementitious materials can effectively reduce carbon emissions compared with pure cement paste. In summary, the quaternary-blended paste has great advantages in terms of durability and sustainability and has good development prospects.

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