Abstract
This paper aims to study the use of Lebanese raw kaolin in the formulation of geopolymers (GP) mortars based on an experimental and numerical approach. Two classes of GP mortars were prepared: the first contained sodium (Na)-based alkali activator, while the second was prepared by adding potassium (K)-based activators. A microstructural characterization was realized before and after the calcination of the raw material. Mechanical characterization of the mortars was conducted by highlighting the impact of the two alkaline solutions used, on tests performed on days 1, 3, 7, 28, 90, and 120. Simultaneously, a three-phased heterogeneous numerical modeling (matrix, aggregates, pores) was used to obtain specific characteristics not accessible experimentally. As main results, the experimental work showed that the binding solutions’ nature and samples’ aging affected the microstructure and, consequently, the mechanical properties. K-based geopolymer mortar presents higher values of mechanical strength than Na-based geopolymer mortar. Moreover, an asymptotic behavior is observed in mechanical characteristics at about 90 days. The numerical results confirmed that micro-defects and porous network have an important impact on Young’s modulus values as well as the presence of the sand phase. The mechanical characteristics of pure binder samples were also obtained numerically. These samples contain natural defects and pores leading it impossible to obtain experimentally the desired characteristics. This work and the associated results confirm that Lebanese raw material can be considered as a sustainable construction material solution for Middle Eastern countries.
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Abbreviations
- GP:
-
Geopolymer
- MK:
-
Metakaolin
- NaOH:
-
Sodium hydroxide
- KOH:
-
Potassium hydroxide
- Na2SiO3 :
-
Sodium silicate
- f′c:
-
Compressive strength
- FEM:
-
Finite element method
References
Davidovits J (2013) Geopolymer cement. A review. GeopolymerInst Tech Papers 21:1–11
Hounsi AD, Lecomte-Nana G, Djeteli G, Blanchart P, Alowanou D, Kpelou P, Napo K, Tchangbédji G, Praisler M (2014) How does Na, K alkali metal concentration change the early age structural characteristic of kaolin-based geopolymers. Ceram Int 40(7):8953–8962
Alonso S, Palomo A (2001) Alkaline activation of metakaolin and calcium hydroxide mixtures: influence of temperature, activator concentration, and solids ratio. Mater Lett 47(1–2):55–62
Favier A, Hotc J, Habert G, Roussel N, De Lacaillerie JBDE (2014) Flow properties of MK-based geopolymer pastes. A comparative study with standard Portland cement pastes. Soft Matter 10(8):1134–1141
De Silva P, Sagoe-Crenstil K, Sirivivatnanon V (2007) Kinetics of geopolymerization: role of Al2O3 and SiO2. CemConcr Res 37(4):512–518
Turner LK, Collins FG (2013) Carbon dioxide equivalent (CO2-e) emissions: a comparison between geopolymer and OPC cement concrete. Constr Build Mater 43:125–130
Firdous R, Stephan D, Djobo JNY (2018) Natural pozzolan based geopolymers: a review on mechanical, microstructural, and durability characteristics. Constr Build Mater 190:1251–1263
Rakhimova NR, Rakhimov RZ (2019) Toward clean cement technologies: a review on alkali-activated fly-ash cement incorporated with supplementary materials. J Non-Cryst Soli 509:31–41
Fu C, Ye H, Zhu K, Fang D, Zhou J (2020) Alkali cation effects on chloride binding of alkali-activated fly ash and metakaolingeopolymers. Cement Concr Compos 114:103721
Zhang M, Guo H, El-Korchi T, Zhang G, Tao M (2013) Experimental feasibility study of geopolymer as the next-generation soil stabilizer. Constr Build Mater 47:1468–1478
Ouellet-Plamondon C, Habert G (2015) Life cycle assessment (LCA) of alkali-activated cements and concretes. In: Handbook of alkali-activated cements, mortars and concretes. Woodhead Publishing: 663-686
Provis JL, Palomo A, Shi C (2015) Advances in understanding alkali-activated materials. CemConcr Res 78:110–125
Alanazi H, Yang M, Zhang D, Gao Z (2017) Early strength and durability of metakaolin-based geopolymer concrete. MagazConcr Res 69(1):46–54
Van Jaarsveld J, Van Deventer JSJ (1999) Effect of the alkali metal activator on the properties of fly ash-based geopolymers. Indus EngChemis Res 38(10):3932–3941
Criado M, Palomo A, Fernández-Jiménez A (2005) Alkali activation of fly ashes. Part 1: effect of curing conditions on the carbonation of the reaction products. Fuel 84(16):2048–2054
Xu H, Van Deventer JSJ (2000) The geopolymerisation of alumino-silicate minerals. Int J Min Process 59(3):247–266
Duxson P, Fernández-Jiménez A, Provis JL, Lukey GC, Palomo A, Van Deventer JS (2007) Geopolymer technology: the current state of the art. J Mater Sci 42(9):2917–2933
Provis JL (2014) Geopolymers and other alkali-activated materials: Why, how, and what? Mater Struct 47(1–2):11–25
Lizcano M, Kim H, Basu S, Radovic M (2012) Mechanical properties of sodium and potassium activated metakaolin-based geopolymers. J Mater Sci 47(6):2607–2616
Henon J, Pennec F, Alzina A, Absi J, Smith DS, Rossignol S (2014) Analytical and numerical identification of the skeleton thermal conductivity of a geopolymer foam using a multi-scale analysis. Comput Mater Sci 82:264–273
Daoud A, Maurel O, Laborderie C (2013) 2D mesoscopic modeling of bar–concrete bond. EngStruct 49:696–706
Fakhari-Tehrani F, Absi J, Allou F, Petit C (2013) Heterogeneous numerical modeling of asphalt concrete through use of a biphasic approach: porous matrix/inclusions. Comput Mater Sci 69:186–196
Fakhari-Tehrani F, Absi J, Allou F, Petit C (2013) Investigation into the impact of the use of 2D/3D digital models on the numerical calculation of the bituminous composites. Comput Mater Sci 79:377–389
Saba M, Georges N, Absi J (2019) Assessment of aluminosilicate raw material used in Lebanon: effect of curing. Mater Des ProcesCommun 1(1):e26. https://doi.org/10.1002/mdp2.26
ASTM C09 (2014) Standard test method for compressive strength of cylindrical concrete specimens. American Society for Testing and Materials International, West Conshohocken
Boonjaeng S, Chindaprasirt P, Pimraksa K (2014) Lime-calcined clay materials with alkaline activation: phase development and reaction transition zone. App Clay Sci 95:357–364
Buncianu D, Tessier-Doyen N, Courrèges F, Absi J (2021) Effect of thermal treatment of a clay-based raw material on porosity and thermal conductivity: experimental approach, image processing and numerical simulation. Eur J Environ CivEng 21(10):1270–1284
Melar J, Renaudin G, Leroux F, Hardy-Dessources A, Nedelec JM, Taviot-Gueho C, Petit E, Steins P, Poulesquen A, Frizon F (2015) The porous network and its interface inside geopolymers as a function of alkali cation and aging. J PhysChem C 119(31):17619–17632
Duxson P, Lukey GC, Separovic F, Van Deventer JS (2005) Effect of alkali cations on aluminum incorporation in geopolymeric gels. IndEngChem Res 44(4):832–839
ASTM C143, C143M–15a (2015) Standard test method for slump of hydraulic-cement concrete. American Society for Testing and Materials International, West Conshohocken
Xu H, Van Deventer JSJ (2000) The geopolymerisation of alumino-silicate minerals. Int J Min Proces 59(3):247–266
Da Silva RT, Dias DP, França FCC, De Salles Guerra RR, De Oliveira LRDC (2018) Metakaolin-based geopolymer mortars with different alkaline activators (Na+ and K+). Constr Build Mater 178:453–461
ASTM C150, C150M (2019) Standard Specification for Portland Cement 1. American Society for Testing and Materials International, West Conshohocken
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Saba, M., Fakhari-Tehrani, F., Michaud, P. et al. Experimental and Numerical Investigation of Sodium- and Potassium-Based Alkali Activator on the Mechanical Properties of Geopolymer-Mortars Using Lebanese Kaolin. Int J Civ Eng 19, 1007–1020 (2021). https://doi.org/10.1007/s40999-021-00627-7
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DOI: https://doi.org/10.1007/s40999-021-00627-7