Alkali-activated cements based on limestone-fly ash: Effect of the MgO-NaOH activation, compressive strength and reaction products

  • Irma Elizabeth Betancourt- Castillo División de Estudios de Posgrado e Investigación, Tecnológico Nacional de México/I.T. de Saltillo
  • Oswaldo Burciaga-Díaz División de Estudios de Posgrado e Investigación, Tecnológico Nacional de México/I.T. de Saltillo
Keywords: Composite cements, Limestone powder, fly ash, alkaline activation, mechanical properties, microstructural characterization


This study investigates the effects of alkaline activation with MgO-NaOH on the compressive strength and reaction products of alkali activated cements of limestone powder (PClz) and Class C fly ash (CV). Results showed that substitutions of 25%<PClz<75% allowed 25-76 MPa at 360 days of curing, obtaining the highest strength with 25%PClz-75%CV and 50%PClz-50%CV with 10 and 12% NaOH-MgO, respectively. The results suggest that PCLz participates in hydration reactions as filler and nucleating agent while CV is the main contributor to the advance of the chemical reactions. X-ray diffraction (XRD), Thermal analysis (TA) and Scanning Electron Microscopy (SEM) indicated the formation of M-S-H, and C, N-A-S-H-type products, in addition to carbonate phases such as hydrotalcite, gaylussite, and pirssonite. Traces of unreacted MgO were not observed indicating its whole incorporation into the reaction products.


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Villágran-Zaccardi, Y., Pareja, R., Rojas, L., Irassar, E., Torres-Acosta, A., Tobón, J., Jhon. V. M. (2022). Overview of cement and concrete production in Latin America and the Caribbean with a focus on the goals of reaching carbon neutrality. RILEM Technical Letters, 7: 30-46. DOI:

Alsalman, A., Assi, L. N., Kareem, R. S., Carter, K., Ziehl, P. (2021). Energy and CO2 emission assessments of alkali-activated concrete and Ordinary Portland Cement concrete: A comparative analysis of different grades of concrete, Cleaner Environmental Systems, 3, 100047, DOI:

Mendoza-Rangel, J. M., Díaz-Aguilera, J. H. (2023). Circular economy in the Latin American cement and concrete industry: a sustainable solution of design, durability, materials, and processes. Revista ALCONPAT, 13(3), 328 - 348. DOI:

Mohamed, O. A., Najm, O., Ahmed, E. (2023) Alkali-activated slag & fly ash as sustainable alternatives to OPC: Sorptivity and strength development characteristics of mortar, Cleaner Materials, 8, 100188, DOI:

Juenger, M. C. G., Snellings, R., Bernal, S. A. (2019), Supplementary cementitious materials: New sources, characterization, and performance insights, Cement and Concrete Research, 122, 257-273, DOI:

Temuujin, J., Surenjav, E., Ruescher, C. H., Vahlbruch, J. (2019), Processing and uses of fly ash addressing radioactivity (critical review), Chemosphere, 216, 866-882, DOI:

Chan, C. L., Zhang, M. (2023), Effect of limestone on engineering properties of alkali-activated concrete: A review, Construction and Building Materials, 362, 129709, DOI:

Ortega-Zavala, D. E., Santana- Carrillo, J. L., Burciaga Díaz, O. Escalante-García. J. I. (2019). An initial study on alkali activated limestone binders. Cement and Concrete Research. 120, 267-278. DOI:

Dehui Wang, Caijun Shi, Nima Farzadnia, Zhenguo Shi, Huangfei Jia, Zhihua Ou. (2018). A review on use of limestone powder in cement-based materials: Mechanism, hydration and microstuctures. Construction and Building Materials. 181, 659-672. DOI:

Fei Jin, Kai Gu, Adel Abdollahzadeh, and Abir Al-Tabbaa (2015). Effects of different reactive MgOs on the hydration of MgO-Activated GGBS paste. J. Mater. Civ. 27. DOI:

Saleh, H. M., Eskander, S. B. (2020). 18 – Innovative cement-based materials for environmental protection and restoration, in: Samui Pijush, Kim, Dookie, R. Iyer Nagesh, Chaudhary Sandeep (Eds.), New Materials in Civil Engineering, Butterworth-Heinemann, pp. 613-641. DOI:

Díaz-Aguilera, J. H. (2024). Estudio del diseño eficiente, optimización, durabilidad y sostenibilidad de una pasta de mortero activado alcalinamente con base en metacaolin y piedra caliza. Doctorado thesis, Universidad Autonóma de Nuevo León.

Xiang, J., Liu,l., Cui, X., He, Y., Zheng, G., Shi, C. (2018). Effect of limestone on rheological, shrinkage and mechanical properties of alkali – Activated slag/fly ash grouting materials. Construction and Building Materials. 191, 1285-1292. DOI:

Burciaga-Díaz, O., Betancourt-Castillo, I. E. (2018). Characterization of novel blast-furnace slag cement pastes and mortars activated with a reactive mixture of MgO-NaOH. Cement and Concrete Research. 105, 54-63. DOI:

Kalinkin, A. M., Gurevich, B. I., Myshenkov. M. S. Chislov, M. V., Kalinkina, E. V., Zvereva. I. A., Cherkezova-Zheleva, Z., Paneva, D., Petkova. V. (2020). Synthesis of Fly Ash-Based Geopolymers: Effect of Calcite Addition and Mechanical Activation. Minerals. 10(9):827. DOI:

Juan, H., Weihao, Z., Wenbin, B., Tingting, H., Junhong, H., Xuefeng, S. (2021). Effect of reactive MgO on hydration and properties of alkali-activated slag pastes with different activators, Construction and Building Materials, 271, 121608, DOI:

Jiang, Y., Jia, Y., Zou, X., Zhang, J., Zou, Y. (2023). Evolution mechanism of the low-carbon MgO-based alkali-activated system under different heat-treatment conditions. Materials Science and Technology, 39(18), 3220–3228. DOI:

Mendes, B. C., Pedroti, L. G., Maurício, C., Vieira, F., Marvila, M., Azevedo, A. R. G. Franco de Carvalho, J. F., Ribeiro. J. C. L. (2021) Application of eco-friendly alternative activators in alkali-activated materials: A review, Journal of Building Engineering, 35, 2021, 102010, DOI:

Hongqiang, M., Xiaomeng L., Xuan, Z., Xiaoyan N., Youliang F. (2022) Effect of active MgO on the hydration kinetics characteristics and microstructures of alkali-activated fly ash-slag materials, Construction and Building Materials, 361, 129677, DOI:

ASTM C188-17. (2017). Standard Test Method for Density of Hydraulic Cement, ASTM international, West Conshohocken, PA.

ASTM C204 – 11. (2011). Standard Test Methods for Fineness of Hydraulic Cement by Air-Permeability Apparatus. ASTM international, West Conshohocken, PA.

Guanqi, W., Biqin, D., Guohao, F., Yanshuai W. (2023). Understanding reactive amorphous phases of fly ash through the acidolysis, Cement and Concrete Composites, 140, 105102, DOI:

Vivek, G., Salman, S., Sandeep, C. (2019) Characterization of different types of fly ash collected from various sources in Central India, Materials Today: Proceedings, 18, Part 7, 5076-5080, DOI:

Shand, M. A. (2006). The Chemistry and Technology of Magnesia, Wiley, Hoboken, NJ, USA. DOI:

Zhang, Z., Scherer, G. W. (2021), Physical and chemical effects of isopropanol exchange in cement-based materials, Cement and Concrete Research, 145, 106461, DOI:

Wang. D, Gao, X., Wang, R., Larsson, S., Benzerzour, M. (2020). Elevated curing temperature-associated strength and mechanisms of reactive MgO-activated industrial by-products solidified soils. Marine Georesources & Geotechnology, 38(6), 659–671. DOI:

Xinyuan K, Bernal, S. A., Provis, J. L. (2017). Uptake of chloride and carbonate by Mg-Al and Ca-Al layered double hydroxides in simulated pore solutions of alkali-activated slag cement, Cement and Concrete Research, 100, 1-13, DOI:

Karunadasa, K. S. P., Manoratne, C. H., Pitawala,H.M., Rajapakse, R.M.G. (2019). Thermal decomposition of calcium carbonate (calcite polymorph) as examined by in-situ high temperature X-ray powder diffraction, Journal of Physics and Chemistry of Solids,134, 21-28. DOI:


Wang, Z., Park, S., Khalid, H. R., Lee, H. K. (2021) Hydration properties of alkali-activated fly ash/slag binders modified by MgO with different reactivity, Journal of Building Engineering, 44, 103252. DOI:

Firdous, R., Hirsch, T., Klimm, D., Lothenbach, B., Stephan, D. (2021). Reaction of calcium carbonate minerals in sodium silicate solutions and its role in alkali-activated systems. Minerals Engineering. 165, 106849. DOI:

Schade, T., Bellmann, F., Middendorf, B. (2022). Quantitative analysis of C-(K)-A-S-H-amount and hydrotalcite phase content in finely ground highly alkali-activated slag/silica fume blended cementitious material, Cement and Concrete Research, 153, 2022, 106706, DOI:

Burciaga-Díaz, O., Betancourt-Castillo, I. E., Escalante-García, J. I. (2023). Limestone and class C fly ash blends activated with binary alkalis of Na2CO3-NaOH and MgO-NaOH: Reaction products and environmental impact. Cement and Concrete Composites, 137, 104949. DOI:

Andrew, R. M. (2019), Global CO2 emissions from cement production, Earth Science Data (1928-2018), DOI:

Mobasher, N., Bernal, S. A., Provis, J. L. (2016) Structural evolution of an alkali sulfate activated slag cement, Journal of Nuclear Materials, Volume 468, 97-104. DOI:

Li, C. H., Jiang, L. (2020). Utilization of limestone powder as an activator for early-age strength improvement of slag concrete, Construct. Build. Mater. 253, 119257. DOI:

How to Cite
Betancourt- Castillo, I. E., & Burciaga-Díaz, O. (2024). Alkali-activated cements based on limestone-fly ash: Effect of the MgO-NaOH activation, compressive strength and reaction products. Revista ALCONPAT, 14(2), 141 - 156.