Comparison of lightweight and normal-weight aggregate concrete

Yıl 2022, Cilt: 13 Sayı: 3, 619 - 626, 30.09.2022

Hatice Çiçek , İsmail Ağa Gönül

https://doi.org/10.24012/dumf.1142146

Öz

In this experimental study, lightweight aggregate concrete (LWAC) and normal-weight aggregate concrete (NWAC) were compared within the contexts of the size of calcium hydroxide (CH) crystals in interfacial transition zone (ITZ), compressive strength, and oven-dry density. Six LWAC and NWAC mixtures were prepared for this study. In LWAC scoria aggregate, in NWAC gravel aggregate were used as coarse aggregate. Thirty-six images obtained from Scanning Electron Microscope (SEM) were used to determine the size of CH crystals in ITZ of LWAC and NWAC. Eighteen test specimens (three for each of the six LWAC and NWAC mixtures) were prepared in 150x300 mm sizes and in the form of cylinders for the compressive strength tests and also eighteen test specimens in 100x100x100 mm sizes and in the form of cubes for the oven-dry density tests. It was determined that the size of CH crystals in ITZ of LWAC is 8.43% less on average, compressive strength of LWAC is 39.09% more on average, and oven-dry density of LWAC is 10.97% less on average than the NWAC’s that has the same volumetric proportions of ingredients. The findings of this study show that lightweight aggregate that has high particle density, angular shape, rough surface texture, and a structure that enables chemical reaction with CH crystals will be beneficial for the ITZ microstructure and properties of concrete. It is considered that these properties should be taken into consideration in the selection of lightweight aggregate for structural concrete production.

Anahtar Kelimeler

Lightweight aggregate concrete, normal-weight aggregate concrete, interfacial transition zone, calcium hydroxide crystals, compressive strength, oven-dry density

Comparison of lightweight and normal-weight aggregate concrete

Öz

In this experimental study, lightweight aggregate concrete (LWAC) and normal-weight aggregate concrete (NWAC) were compared within the contexts of the size of calcium hydroxide (CH) crystals in interfacial transition zone (ITZ), compressive strength, and oven-dry density. Six LWAC and NWAC mixtures were prepared for this study. Thirty-six images obtained from Scanning Electron Microscope (SEM) were used to determine the size of CH crystals in ITZ of LWAC and NWAC. Eighteen test specimens (three for each of the six LWAC and NWAC mixtures) were prepared in 150x300 mm sizes and in the form of cylinders for the compressive strength tests and also eighteen test specimens in 100x100x100 mm sizes and in the form of cubes for the oven-dry density tests. It was determined that the size of CH crystals in ITZ of LWAC is 8.43% less than (on average), compressive strength of LWAC is 39.09% more than (on average), and oven-dry density of LWAC is 10.97% less than (on average) the NWAC’s that has the same volumetric proportions of ingredients. The findings of this study show that lightweight aggregate that has high particle density, angular shape, rough surface texture, and a structure that enables chemical reaction with CH crystals will be beneficial for the ITZ microstructure and properties of concrete. It is considered that these properties should be taken into consideration in the selection of lightweight aggregate for structural concrete production.

Anahtar Kelimeler

Lightweight aggregate concrete, normal-weight aggregate concrete, interfacial transition zone, calcium hydroxide crystals, compressive strength, compressive strength, oven-dry density

Kaynakça

• P. K. Mehta and P. J. M. Monteiro, Concrete - Microstructure, Properties, and Materials. Third ed., New York, NY, USA: McGraw-Hill, 2006.
• E. Gallucci and K. Scrivener, “Crystallisation of calcium hydroxide in early age model and ordinary cementitious systems,” Cem. Concr. Res., vol. 37, pp. 492-501, 2007.
• H. Gönül, “Bazalt skoriasının taşıyıcı yarı hafif beton üretiminde kullanımı / Use of basaltic scoria for produce of semi lightweight concrete,” Ph.D. dissertation, Dept. of Architecture, Gazi Univ., Ankara, 2008.
• M. Ayhan, H. Gönül, İ. A. Gönül, and A. Karakuş, “Effect of basic pumice on morphologic properties of interfacial transition zone in load-bearing lightweight / semi-lightweight concretes,” Constr. Build. Mater., vol. 25, pp. 2507-2518, 2011.
• V. Nežerka, P. Bílý, V. Hrbek, and J. Fládr, “Impact of silica fume, fly ash, and metakaolin on the thickness and strength of the ITZ in concrete,” Cem. Concr. Compos., vol. 103, pp. 252-262, 2019.
• J. Skalny, J. Gebauer, and I. Odler, eds., Materials Science of Concrete: Calcium Hydroxide in Concrete. Westerville, USA: The American Ceramic Society, 2001.
• C. Carde and R. François, “Effect of the leaching of calcium hydroxide from cement paste on the mechanical and physical properties,” Cem. Concr. Res., vol. 27, pp. 539-550, 1997.
• N. Hernandez, J. Lizarazo-Marriaga, and M. A. Rivas, “Petrographic characterization of Portlandite crystal sizes in cement pastes affected by different hydration environments,” Constr. Build. Mater., vol. 182, pp. 541-549, 2018.
• T. Sacki and P. J. M. Monteiro, “A model to predict the amount of calcium hydroxide in concrete containing mineral admixtures,” Cem. Concr. Res., vol. 35, pp. 1914-1921, 2005.
• J. Marchand, D. P. Bentz, E. Samson, and Y. Maltais, “Influence of calcium hydroxide dissolution on the transport properties of hydrated cement systems,” in Materials Science of Concrete: Calcium Hydroxide in Concrete, J. Skalny, J. Gebauer, and I. Odler, eds., Westerville, USA: The American Ceramic Society, 2001, pp. 113-129.
• Z. Yan-Rong, K. Xiang-Ming, L. Zi-Chen, L. Zhen-Bao, Z. Qing, D. Bi-Qin, and X. Feng, “Influence of triethanolamine on the hydration product of portlandite in cement paste and the mechanism,” Cem. Concr. Res., vol. 87, pp. 64-76, 2016.
• T. Müller, C. Krämer, C. Pritzel, R. Bornemann, T. L. Kowald, R. H. F. Trettin, and P. H. Bolívar, “Influence of cocamidopropyl betaine on the formation and carbonation of portlandite – A microscopy study,” Constr. Build. Mater., vol. 163, pp. 793-797, 2018.
• W. Kunther, S. Ferreiro, and J. Skibsted, “Influence of the Ca/Si ratio on the compressive strength of cementitious calcium–silicate–hydrate binders,” J. Mater. Chem. A, vol. 5, pp. 17401-17412, 2017.
• S. Diamond, “The microstructure of cement paste and concrete––a visual primer,” Cem. Concr. Compos., vol. 26, pp. 919-933, 2004.
• K. Wu, H. Shi, L. Xu, G. Ye, and D. G. Schutter, “Microstructural characterization of ITZ in blended cement concretes and its relation to transport properties,” Cem. Concr. Res., vol. 79, pp. 243-256, 2016.
• J. S. Belkowitz and D. Armentrout, “An investigation of nano silica in the cement hydration process,” presented at the Concrete Sustainability Conference, USA, 2010.
• Q. Ye, Z. Zhang, D. Kong, and R. Chen, “Influence of nano-SiO2 addition on properties of hardened cement paste as compared with silica fume,” Constr. Build. Mater., vol. 21, pp. 539-545, 2007.
• J. J. Thomas and H. Jennings, “Materials of cement science primer: The science of concrete,” Northwestern University Infrastructure Technology Institute, USA, Rep. Project A474, 2009.
• T. Slamečka and F. Škvára, “The effect of water ratio on microstructure and composition of the hydration products of Portland cement pastes,” Ceram. Silik., vol. 46, no. 4, pp. 152-158, 2002.
• M. Alexander and S. Mindess, Aggregates in concrete. New York, NY, USA: Taylor & Francis, 2005.
• A. A. SamsonDuna, “Utilization of scoria as aggregate in lightweight concrete,” Int. J. Eng. Res., vol. 6, no. 1, pp. 34-37, 2017.
• T. J. Gomes, “Structural lightweight concrete produced with volcanic scoria from São Miguel Island,” Instituto Superior Técnico, 2015.
• I. Lau, S. Setunge, and N. Gamage, “Properties of concrete using scoria lightweight aggregate concrete,” in 23rd Australasian Conference on the Mechanics of Structures and Materials, Lismore, Australia, 9-12 December 2014, pp. 95-100.
• A. Kılıç, C. D. Ati, A. Teymen, O. Karahan, and K. Arı, “The effects of scoria and pumice aggregates on the strengths and unit weights of lightweight concrete,” Sci. Res. Essays, vol. 4, no.10, pp. 961-965, 2009.
• K. M. A. Hossain, “Blended cement and lightweight concrete using scoria: mix design, strength, durability and heat insulation characteristics,” Int. J. Phys. Sci., vol. 1, no. 1, pp. 5-16, 2006.
• A. Kılıç, C. D. Atiş, E. Yaşar, and F. Özcan, “High-strength lightweight concrete made with scoria aggregate containing mineral admixtures,” Cem. Concr. Res., vol. 33, pp. 1595-1599, 2003.
• E. Yaşar, C. D. Atiş, A. Kılıç, and H. Gülsen, “Strength properties of lightweight concrete made with basaltic pumice and fly ash,” Mater. Lett., vol. 57, pp. 2267-2270, 2003.
• M. R. Moufti, A. A. Sabtan, O. R. El-Mahdy, and W. M. Shehata, “Assessment of the industrial utilization of scoria materials in Central Harrat Rahat, Saudi Arabia,” Eng. Geol., vol. 57, pp. 155-162, 2000.
• The European Union, “Properties of LWAC made with natural lightweight aggregates,” Eurolightcon BE96-3942/R17, pp. 8-35, 2000.
• Testing hardened concrete - Part 1: Shape, dimensions and other requirements for specimens and moulds, TS EN 12390-1, 2002.
• Testing hardened concrete - Part 2: Making and curing specimens for strength tests, TS EN 12390-2, 2002.
• Testing hardened concrete - Part 3: Compressive strength of test specimens, TS EN 12390-3, 2003.
• Testing hardened concrete - Part 4: Compressive strength - Specification for testing machines, TS EN 12390-4, 2002.
• Testing hardened concrete - Part 7: Density of hardened concrete, TS EN 12390-7, 2002.
• P. C. Aitcin, “Portland cement,” in Science and Technology of Concrete Admixtures, P. C. Aitcin and R. J. Flatt, eds., UK: Woodhead Publishing, 2016, pp. 27-53.
• M. A. Caldarone, High-strength concrete: A Practical Guide. New York, NY, USA: Taylor & Francis, 2009.
• Lightweight aggregates - Part 1: Lightweight aggregates for concrete, mortar and grout, TS 1114 EN 13055-1, 2004.
• L. Gündüz and İ. Uğur, “The effects of different fine and coarse pumice aggregate / cement ratios on the structural concrete properties without using any admixtures,” Cem. Concr. Res., vol. 35, pp. 1859-1864, 2005.