Impact of Activator Ratio on Fly Ash-Based Geopolymer Concrete

Authors

  • Ajmal Ramadhany University of Tanjungpura
  • Herwani Herwani University of Tanjungpura
  • Faisal Faisal University of Tanjungpura

DOI:

https://doi.org/10.26418/jts.v25i1.88511

Keywords:

Age Variation, NaOH Solution, Activator, Geopolymer Concrete, Fly Ash

Abstract

Geopolymer concrete is made by activating raw materials high in silica and alumina using alkaline activators. This material substitutes conventional Portland cement concrete by incorporating industrial waste materials like fly ash or metakaolin, which are recognized for reduced carbon emissions and superior chemical resistance. This study experimentally investigates the effect of the activator ratio (NaOH/Na₂SiO₃) on the alkali-silica reaction and the mechanical properties of geopolymer concrete made from fly ash, aiming to optimize the performance of this sustainable construction material. The experiment assesses various parameters, such as slump, volume weight, compressive strength, splitting tensile strength, and elastic modulus, using a constant 10M molar concentration for the activator solution with activator ratios of 1/2, 1/3, 1/4, and 1/5. The specimens used for the tests were cylindrical, measuring 10 cm x 20 cm for compressive strength tests and 15 cm x 30 cm for tests on split tensile strength and elastic modulus. Compressive strength was tested at 7, 14, and 28 days, while split tensile strength and elastic modulus were tested at 28 days. Results announced that increasing the Na₂SiO₃ concentration in the activator solution significantly affected the properties of geopolymer concrete. The optimal NaOH/Na₂SiO₃ ratio was found to be 1/5.

References

Antonia, E. J., Pandohop Gawei, A. B., Meilawaty, O., Waluyo, R., & Lendra, L. (2023). Analisis Kuat Tekan Beton Menggunakan Agregat Lokal di Kecamatan Tewah Kabupaten Gunung Mas. Jurnal Serambi Engineering, 8(4), 7541-7546.

Duxson, P., Fernández-Jiménez, A., Provis, J. L., Lukey, G. C., Palomo, A., & van Deventer, J. S. (2007). Geopolymer Technology: The Current State of the Art. Journal of Materials Science, 42, 2917-2933.

Ganesan, N., Abraham, R., Raj, S. D., & Sasi, D. (2014). Stress–Strain Behaviour of Confined Geopolymer Concrete. Construction and Building Materials, 73, 326-331.

Hossain, M. U., Poon, C. S., Lo, I. M., & Cheng, J. C. (2017). Comparative LCA on Using Waste Materials in the Cement Industry: A Hong Kong Case Study. Resources, Conservation and Recycling, 120, 199-208.

Kalra, M., & Mehmood, G. (2018). A Review Paper on the Effect of Different Types of Coarse Aggregate on Concrete. In IOP Conference Series: Materials Science and Engineering, 431(8), 082001. IOP Publishing.

Lehne, J., & Preston, F. (2018). Making Concrete Change: Innovation in Low-Carbon Cement and Concrete. Chatham House Report, 13, 1-122.

Nordin, N., Abdullah, M. M. A. B., Tahir, M. F. M., Sandu, A. V., & Hussin, K. (2016). Utilization of Fly Ash Waste as Construction Material. International Journal of Conservation Science, 7(1), 161.

Okechi, I. K., Aguayo, F., & Torres, A. (2022). Coefficient of Thermal Expansion of Concrete Produced with Recycled Concrete Aggregates. Journal of Civil Engineering and Construction, 11(2), 65-74.

Pacheco-Torgal, F., Castro-Gomes, J., & Jalali, S. (2008). Alkali-Activated Binders: A Review: Part 1. Historical Background, Terminology, Reaction Mechanisms and Hydration Products. Construction and Building Materials, 22(7), 1305-1314.

Pane, I., Imran, I., & Budiono, B. (2018). Compressive Strength of Fly Ash-Based Geopolymer Concrete with a Variable of Sodium Hydroxide (NaOH) Solution Molarity. In MATEC Web of Conferences, 147, 01004. EDP Sciences.

Risdanareni, P., Ekaputri, J. J., & Al Bakri Abdullah, M. M. (2015). Effect of alkaline Activator Ratio to Mechanical Properties of Geopolymer Concrete with Trass as Filler. Applied Mechanics and Materials, 754, 406-412.

Salain, I. M. A. K., Wiryasa, M. N. A., & Pamungkas, I. N. M. M. A. (2021). Kuat Tekan Beton Geopolimer Menggunakan Abu Terbang. Jurnal Spektran, 9(1), 76-84.

Tabsh, S. W., & Alhoubi, Y. (2022). Experimental Investigation of Recycled Fine Aggregate from Demolition Waste in Concrete. Sustainability, 14(17), 10787.

Watari, T., Cao, Z., Hata, S., & Nansai, K. (2022). Efficient Use of Cement and Concrete to Reduce Reliance on Supply-Side Technologies for Net-Zero Emissions. Nature Communications, 13(1), 4158.

Wojtacha-Rychter, K., Kucharski, P., & Smolinski, A. (2021). Conventional and Alternative Sources of Thermal Energy in the Production of Cement—An Impact on CO2 Emission. Energies, 14(6), 1539.

Xu, D., Cui, Y., Li, H., Yang, K., Xu, W., & Chen, Y. (2015). On the Future of Chinese Cement Industry. Cement and Concrete Research, 78, 2-13.

Yao, Z. T., Ji, X. S., Sarker, P. K., Tang, J. H., Ge, L. Q., Xia, M. S., & Xi, Y. Q. (2015). A Comprehensive Review on the Applications of Coal Fly Ash. Earth-Science Reviews, 141, 105-121.

Zhaurova, M., Soukka, R., & Horttanainen, M. (2021). Multi-Criteria Evaluation of CO2 Utilization Options for Cement Plants Using the Example of Finland. International Journal of Greenhouse Gas Control, 112, 103481.

Živica, V., Palou, M. T., & Križma, M. (2015). Geopolymer Cements and Their Properties: A Review. Build. Res. J, 61(2), 85-100.

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Published

2025-03-17

Issue

Section

Vol 25, No 1 (2025): Vol 25, No 1 (2025): JURNAL TEKNIK SIPIL EDISI FEBRUARI 2025