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  • Ezgi Örklemez Erciyes Üniversitesi
  • Serhan İlkentapar Erciyes Üniversitesi, Mühendislik Fakültesi, İnşaat Mühendisliği Bölümü



Diatomite, Fly Ash, Geopolymer, Abrasion Resistance, Elevated Temperature Resistance


In recent years, due to both environmental concerns and international agreements (European Green Deal), it is aimed to reduce CO2 emissions from cement production and to develop alternative products with less ecological footprints. For this reason, geopolymer binders are among the products that can be an alternative to cement. Fly ash used in geopolymer binder systems comes out as a waste product from thermal power plants and creates environmental concerns. For this reason, it is of great importance that fly ash is used in geopolymer systems, which can be an alternative to cement-based systems and become an environmentally sustainable material. Improving the mechanical properties of fly ash-based geopolymers by various methods has recently become important. This study investigated the effect of diatomite substitution on the physical and mechanical properties of geopolymer samples produced with F-class fly ash. In the mixtures, diatomite was substituted at 1%, 2%, 3%, 4%, and 5% by weight of fly ash and used as a binder. Sodium hydroxide (NaOH) was chosen as the activator, and it was used to contain 10% Na+ by weight according to the binder material. The thermal cure was applied to the produced geopolymer samples at 60°C for 24, 48, and 72 hours. Unit weight, flexural and compressive strength, abrasion resistance, and resistance to high temperatures were tested on geopolymer samples. In addition, FESEM images were taken of the geopolymer paste samples to examine the microstructure of the samples. According to the results obtained, 1%, 2%, and 3% diatomite substitution in geopolymer mortars increased flexural and compressive strengths. The highest compressive strength value (42.4 MPa) was obtained in mortars containing 3% diatomite. As a result of FESEM images, it was seen that the geopolymer with 3% diatomite substitution had a more dense and compact microstructure compared to the control sample. It was concluded that while 3% diatomite substitution increased wear resistance, it did not increase resistance to elevated temperatures.


C. L. Sabine et al., “The Oceanic Sink for Anthropogenic CO2,” Science (1979), vol. 305, no. July, pp. 5–12, 2004, doi: DOI: 10.1126/science.1097403.

D. N. Huntzinger and T. D. Eatmon, “A life-cycle assessment of Portland cement manufacturing: comparing the traditional process with alternative technologies,” J Clean Prod, vol. 17, no. 7, pp. 668–675, 2009, doi: 10.1016/j.jclepro.2008.04.007.

H. Li et al., “Sustainable resource opportunity for cane molasses: Use of cane molasses as a grinding aid in the production of Portland cement,” J Clean Prod, vol. 93, pp. 56–64, 2015, doi: 10.1016/j.jclepro.2015.01.027.

R. A. Feely et al., “Impact of anthropogenic CO2 on the CaCO3 system in the oceans,” Science (1979), vol. 305, no. 5682, pp. 362–366, Jul. 2004, doi: 10.1126/SCIENCE.1097329.

L. Imtiaz et al., “Life cycle impact assessment of recycled aggregate concrete, geopolymer concrete, and recycled aggregate-based geopolymer concrete,” Sustainability (Switzerland), vol. 13, no. 24, 2021, doi: 10.3390/su132413515.

S. K. John, Y. Nadir, and K. Girija, “Effect of source materials, additives on the mechanical properties and durability of fly ash and fly ash-slag geopolymer mortar: A review,” Constr Build Mater, vol. 280, p. 122443, Apr. 2021, doi: 10.1016/J.CONBUILDMAT.2021.122443.

S. Saha and C. Rajasekaran, “Enhancement of the properties of fly ash based geopolymer paste by incorporating ground granulated blast furnace slag,” Constr Build Mater, vol. 146, pp. 615–620, Aug. 2017, doi: 10.1016/J.CONBUILDMAT.2017.04.139.

A. Sathonsaowaphak, P. Chindaprasirt, and K. Pimraksa, “Workability and strength of lignite bottom ash geopolymer mortar,” J Hazard Mater, vol. 168, no. 1, pp. 44–50, 2009, doi: 10.1016/j.jhazmat.2009.01.120.

K. Somna, C. Jaturapitakkul, P. Kajitvichyanukul, and P. Chindaprasirt, “NaOH-activated ground fly ash geopolymer cured at ambient temperature,” Fuel, vol. 90, no. 6, pp. 2118–2124, Jun. 2011, doi: 10.1016/J.FUEL.2011.01.018.

F. Pacheco-Torgal, J. Castro-Gomes, and S. Jalali, “Alkali-activated binders: A review. Part 2. About materials and binders manufacture,” Constr Build Mater, vol. 22, no. 7, pp. 1315–1322, 2008, doi: 10.1016/j.conbuildmat.2007.03.019.

A. Palomo, M. W. Grutzeck, and M. T. Blanco, “Alkali-activated fly ashes: A cement for the future,” Cem Concr Res, vol. 29, no. 8, pp. 1323–1329, Aug. 1999, doi: 10.1016/S0008-8846(98)00243-9.

J. C. Swanepoel and C. A. Strydom, “Utilisation of fly ash in a geopolymeric material,” Applied Geochemistry, vol. 17, no. 8, pp. 1143–1148, Aug. 2002, doi: 10.1016/S0883-2927(02)00005-7.

N. Toniolo and A. R. Boccaccini, “Fly ash-based geopolymers containing added silicate waste. A review,” Ceram Int, vol. 43, no. 17, pp. 14545–14551, Dec. 2017, doi: 10.1016/J.CERAMINT.2017.07.221.

U. Durak, O. Karahan, B. Uzal, S. İlkentapar, and C. D. Atiş, “Influence of nano SiO2 and nano CaCO3 particles on strength, workability, and microstructural properties of fly ash-based geopolymer,” Structural Concrete, vol. 22, no. S1, pp. E352–E367, Jan. 2021, doi: 10.1002/SUCO.201900479.

C. Bagci, G. P. Kutyla, and W. M. Kriven, “Fully reacted high strength geopolymer made with diatomite as a fumed silica alternative,” Ceram Int, vol. 43, no. 17, pp. 14784–14790, 2017, doi: 10.1016/j.ceramint.2017.07.222.

T. Sinsiri, T. Phoo-ngernkham, N. Ratchasima, and V. Sata, “The effects of replacement fly ash with diatomite in geopolymer mortar,” Computers and Concrete, vol. 9, no. 6, pp. 427–439, 2012, doi: 10.12989/cac.2012.9.6.427.

TS EN 196-1, Methods of testing cement—part:1 determination of strength. TSE, 2016.

T. Standard, “Turkish Standard Ts 2824 En 1338,” no. 112, 2005.

M. Sciences, T. Phoo-ngernkham, P. Chindaprasirt, V. Sata, and T. Sinsiri, “High calcium fly ash geopolymer containing diatomite as additive,” Indian Journal of Engineering & Materials Sciences, vol. 20, no. August, pp. 310–318, 2013.

S. İlkentapar, E. Örklemez, E. Üniversitesi, M. Fakültesi, İ. Mühendisliği, and İ. Yazar, “Uçucu Kül Esaslı Geopolimer Harçlara Diatomit İkamesinin Isı İletkenliğe Etkisi The Effect of Diatomite Addition on Fly Ash Based Geopolymer Mortars on Thermal Conductivity Values,” Erciyes University Journal of Institue of Science and Technology, vol. 36, p. 2020, 2020.

C. D. Atiş, E. B. Görür, O. Karahan, C. Bilim, S. İlkentapar, and E. Luga, “Very high strength (120 MPa) class F fly ash geopolymer mortar activated at different NaOH amount, heat curing temperature and heat curing duration,” Constr Build Mater, vol. 96, pp. 673–678, Oct. 2015, doi: 10.1016/J.CONBUILDMAT.2015.08.089.

Messina, Ferone, F. Colangelo, Roviello, and Cioffi, “Alkali activated waste fly ash as sustainable composite: Influence of curing and pozzolanic admixtures on the early-age physico-mechanical properties and residual strength after exposure at elevated temperature,” Compos B Eng, vol. 132, pp. 161–169, Jan. 2018, doi: 10.1016/J.COMPOSITESB.2017.08.012.

E. ÖRKLEMEZ, “Uçucu Kül TabanliGeopoli̇mer HarçlardDi̇atomiİkamesi̇ni̇Fi̇zi̇ksel VeMekani̇Özelli̇kleri̇Üzeri̇Etki̇leri̇ni̇n Araştirilmasi,” Erciyes University, 2019.

A. M. Neville, Properties of Concrete Fifth Edition. 2011. doi: 10.4135/9781412975704.n88.

S. İlkentapar, C. D. Atiş, O. Karahan, and E. B. Görür Avşaroğlu, “Influence of duration of heat curing and extra rest period after heat curing on the strength and transport characteristic of alkali activated class F fly ash geopolymer mortar,” Constr Build Mater, vol. 151, pp. 363–369, Oct. 2017, doi: 10.1016/J.CONBUILDMAT.2017.06.041.

M. Sivasakthi, R. Jeyalakshmi, N. P. Rajamane, and R. Jose, “Thermal and structural micro analysis of micro silica blended fly ash based geopolymer composites,” J Non Cryst Solids, vol. 499, no. March, pp. 117–130, 2018, doi: 10.1016/j.jnoncrysol.2018.07.027.

M. Sivasakthi, R. Jeyalakshmi, and N. P. Rajamane, “Fly ash geopolymer mortar: Impact of the substitution of river sand by copper slag as a fine aggregate on its thermal resistance properties,” J Clean Prod, vol. 279, p. 123766, 2021, doi: 10.1016/j.jclepro.2020.123766.

E. D. Rodríguez, S. A. Bernal, J. L. Provis, J. Paya, J. M. Monzo, and M. V. Borrachero, “Effect of nanosilica-based activators on the performance of an alkali-activated fly ash binder,” Cem Concr Compos, vol. 35, no. 1, pp. 1–11, 2013, doi: 10.1016/j.cemconcomp.2012.08.025.

P. S. Deb, P. K. Sarker, and S. Barbhuiya, “Effects of nano-silica on the strength development of geopolymer cured at room temperature,” Constr Build Mater, vol. 101, pp. 675–683, 2015, doi: 10.1016/j.conbuildmat.2015.10.044.

J. E. Oh, P. J. M. Monteiro, S. S. Jun, S. Choi, and S. M. Clark, “The evolution of strength and crystalline phases for alkali-activated ground blast furnace slag and fly ash-based geopolymers,” Cem Concr Res, vol. 40, no. 2, pp. 189–196, 2010, doi: 10.1016/j.cemconres.2009.10.010.



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