Chemical and Engineering Properties of Blended Cement Containing Micro- and Nano-silica

Hamdy El-Didamony Ahmed; Berry Abd El-Ghani Sabrah; Saleh Abd El-Aleem Mohamed; Nashwa Mohamed Mostafa

doi:doi:10.11648/j.ajche.20170505.13

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Chemical and Engineering Properties of Blended Cement Containing Micro- and Nano-silica

Hamdy El-Didamony Ahmed, Berry Abd El-Ghani Sabrah, Saleh Abd El-Aleem Mohamed, Nashwa Mohamed Mostafa

Published in American Journal of Chemical Engineering (Volume 5, Issue 5)

Received: 31 August 2017 Accepted: 19 September 2017 Published: 3 November 2017

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Abstract

Nano-technology (NT) and nano-materials (NMs) has attracted considerable scientific attention, due to the new potential uses of nano-particles (NPs), which can change the concrete world. There is a great interest in replacing a long time used materials in concrete structure by NMs to improve the different properties of concrete. In this study, the hydration characteristics and microstructure of cement pastes and mortars with and without nano-silica (NS) were studied. Blended cement mix containing 10 mass, % silica fume (SF) was prepared, then the cement mix was partially replaced by NS up 1.5 mass, %. The results show that, NS increases the water of consistency and final setting time The values of chemically combined water, free lime, bulk density and compressive strength prove that, NS up to 1% seems to be an effective mineral additive for blending with OPC to improve its chemical and engineering properties. This is mainly attributed to that; NS behaves not only as filler to improve microstructure, but also as pozzolanic material (PZM). The formation of more hydrated silicates in presence of NS was confirmed by XRD, DTA, IR and SEM examinations. At 1.5 mass, % NS, the density and strength are reduced but still higher than those of 0.0 and 0.5% NS. Also, the results indicate that, the substitution of blended cement mix (OPC+10% SF) with 1 mass, % NS gives a reasonable hydration characteristics and improved engineering properties more than those of 0.0 and 0.5% NS at all hydration ages up to 90 days. Therefore, this level of NS is suggested to be the most suitable replacement level.

Published in	American Journal of Chemical Engineering (Volume 5, Issue 5)
DOI	10.11648/j.ajche.20170505.13
Page(s)	111-121
Creative Commons	This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.
Copyright	Copyright © The Author(s), 2017. Published by Science Publishing Group

Keywords

Microsilica, Nanosilica, Setting Times, OPC, Chemical Properties, Engineering Properties and Microstructure

References

[1]	L. G. Li, Z. H. Huang, J. Zhu, A. K. H. Kwan, H. Y. Chen, "Synergistic effects of micro-silica and nano-silica on strength and microstructure of mortar", Construction and Building Materials 140 (2017), pp. 229–238.
[2]	F. Pacheco-Torgal, S. Miraldo, Y. Ding, J. A. Labrincha, Targeting HPC with the help of nanoparticles: an overview, Constr. Build. Mater., 38 (2013), pp. 365–370.
[3]	Jo B. W, Kim C. H, Tae G. H, Park J. B. "Characteristics of cement mortar with nano- SiO₂ particles". Constr. Build. Mater. 21(6); (2007), 1351–1355.
[4]	H. A. Abdel-Gawwad, S. Abd El-Aleem, “Effect of Reactive Magnesia on the Properties of Alkali Activated Slag Cement Pastes”, International Journal of Science and Research (IJSR), 4 (5), 2015, 1197-1204.
[5]	Mehta PK. “Concrete, structure, properties and materials” Editor WJ. Hall; (1986).
[6]	V. S. Mane, P. S. Yadav, Y. S. Dudhagamwar, P. S. Gawande, “Study on Nanotechnology in Civil Engineering Structures”, International Advanced Research Journal in Science, Engineering and Technology.
[7]	Li H., Xiao H, Yuan J., Ou J. “Microstructure of cement mortar with nano-particles” Composites: Part B 35, (2004), pp. 185–189.
[8]	Givi A. N., Rashid. S. A, A. Aziz F. N, Salleh M. A. M “Experimental investigation of the size effects of SiO₂ nano-particles on the mechanical properties of binary blended concrete” Composites: Part B 41 (2010), pp. 673–677.
[9]	Mahender B., Ashok B., "Effect of Nanosilica on the compressive strength of concrete", International Journal of Professional Engineering Studies, 8, 2 (2017).
[10]	S. Abd. El. Aleem, M. Heikal, W. M. Morsi “Hydration characteristic, thermal expansion and microstructure of cement containing nano-silica”, Constr. Build. Mater.; 59, 2014, 151–160.
[11]	Senff L., Labrincha J. A, Ferreira V. M., Hotza D., and Repette W. L., Constr. Build. Mater. 23 (2009) 2487–2491.
[12]	Qing Y., Zenan Z., Li S., and Rongshen C. “A comparative study on the pozzolanic activity between nano- SiO₂ and silica fume” J Wuhan Univ. Technol. Matere Sci. Ed 21(3) (2008), pp. 153–7.
[13]	Zyganitidis I., Stefanidou M., Kalfagiannis N., Logothetidis S. “Nano-mechanical characterization of cement-based pastes enriched with SiO₂ nano-particles” Mat. Sci. Eng. B 176 (9); (2011), pp. 1580–1584.
[14]	Ulm F. J., Vandamme M. “Probing nanostructure of C–S–H by micro- mechanics based indentation techniques” Editors: Bittnar Z., Bartos P. J. M., Nemecek J., Smilauer V., Zeman J. Nano-technology in Construction: Proceedings of the NICOM3 Prague; (2009), pp. 43–54.
[15]	Quercia G., Brouwers H. J. H. “Application of nano-silica in concrete mixtures” 8th PhD Symposium in Kgs. Lyngby Denmark;( 2010).
[16]	Corr D., Shah S. P. “Concrete materials science at the nanoscale” Applications of Nanotechnology in concrete Design Edited by Dhir R. K., Newlands M. D., Csetenyi L. J; (2005), pp. 1–12.
[17]	Jemimah Carmichae M., Prince Arulraj G., “Strength and permeability studies on concrete with Nano-Cement”, IJCIET, 8, (2017), pp. 132–139.
[18]	Meral Oltulu., Remzi Sahin., “Single and combined effects of nano-SiO₂, nano-Al₂O₃ and nano-Fe₂O₃ powders on compressive strength and capillary permeability of cement mortar containing silica fume”, Materials Science and Engineering A., 528., (2011), pp. 7012–7019.
[19]	Zhang P., Wana J., Wang K., Li Q., "Influence of nano-SiO₂ on properties of fresh and hardened high performance concrete: A state-of-the-art review", Constr. Build. Mater., 148, (2017), pp. 648–658.
[20]	Amr A. Essawy and S. Abd El. Aleem “Physico-mechanical properties, potent adsorptive and photocatalytic efficacies of sulfate resisting cement blends containing micro silica and nano-TiO₂”, Construction and Building Materials 52, 2014, 1–8.
[21]	Heikal, M., El-Didamony, H., Sokkary, T. M. and Ahmed, I. A., ''Behavior of composite cement pastes containing micro-silica and fly ash at elevated temperature'', Constr. Build. Mater., 38, (2013), pp. 1180–1190.
[22]	Pokar Amitkumar R., Pokar Narendra R., “Application of Silica Fume and Nanosilica in Cement and Concrete – A Review”, 3, 5, (2016), pp. 723-724.
[23]	Haruehansapong S., Pulngern T., and Chucheepsakul S., “Effect of the particle size of nanosilica on the compressive strength and the optimum replacement content of cement mortar containing Nano-SiO₂” Construction and Building Materials, 50, (2014), pp. 471–477.
[24]	Zemei Wu, Kamal Henri Khayat, and Caijun Shi., "Effect of nano-SiO₂ particles and curing time on development of fiber-matrix bond properties and microstructure of ultra-high strength concrete", Cement and Concrete Research, 95, (2017), pp. 247–256.
[25]	Sattawat Haruehansapong, Tawich Pulngern and Somchai Chucheepsakul., "Effect of Nanosilica Particle Size on the Water Permeability, Abrasion Resistance, Drying Shrinkage, and Repair Work Properties of Cement Mortar Containing Nano-SiO₂", Hindawi Advances in Materials Science and Engineering, (2017), 11 pages.
[26]	Qing, Y., Zenan, Z., Li, S. and Rongshen, C. A., "A comparative study on the pozzolanic activity between nano-SiO₂ and silica fume", J. Wuhan Univ. Technol. Mater. Sci., Ed. 21, (2006), pp. 153-157.
[27]	Nazari A., Riahi S. “The effects of SiO₂ nanoparticles on physical and mechanical properties of high strength compacting concrete” Compos. Part B: Eng. 42 (2011) 570–578.
[28]	L. Senff, J. A. Labrincha, V. M. Ferreira, D. Hotza, W. L. Repette, Construct. Build. Mater., 23, (2009), pp. 2487–2491.
[29]	S. Abd El-Aleem, and A. Ragab, "Physico-Mechanical Properties and Microstructure of Blended Cement Incorporating Nano-Silica" International Journal of Engineering Research & Technology, 3 (2014), pp. 339-358.
[30]	Abd-El-Eziz M. A. and Heikal M. “Hydration characteristics and durability of cements containing fly ash and limestone subjected to Qaron’s Lake Water” Adv. Cem. Res., 21(3); (2009), pp. 91-99.
[31]	M. Heikal, S. Abd El-Aleem, and W M. Morsi, “Characteristics of blended cements containing nano-silica” HBRC Journal (9) (2013), pp. 243–255.
[32]	Magdy A. Abdelaziz, Saleh Abd El-Aleem and Wagih M. Menshawy, “Effect of fine materials in local quarry dusts of limestone and basalt on the properties of Portland cement pastes and mortars”, International Journal of Engineering Research & Technology (IJERT), 3(6), ( 2014), pp. 1038-1056.
[33]	ASTM Designation: C191, Standard method for normal consistency and setting of hydraulic cement, ASTM Annual Book of ASTM Standards, (2008).
[34]	M. A. Abd-El. Aziz, S. Abd. El. Aleem, and M. Heikal “Physico-chemical and mechanical characteristics of pozzolanic cement pastes and mortars hydrated at different curing temperatures” Constr. Build. Mater. 26; (2012), pp. 310–316.
[35]	H. El-Didamony, M. Abd-El. Eziz, and S. Abd. El. Aleem, Hydration and durability of sulfate resisting and slag cement blends in Qarons “Lake water”, Cem. Concr. Res., 35; (2005), pp. 1592-1600.
[36]	H. W. Sufee, “Comprehensive studies of different blended cements and steel corrosion performance in presence of admixture”, Ph.D. Thesis, Faculty of Science, Fayoum University, Fayoum, Egypt) 2007).
[37]	Abd-El-Eziz M. A. and Heikal M. “Hydration characteristics and durability of cements containing fly ash and limestone subjected to Qaron’s Lake Water” Adv. Cem. Res., 21(3); (2009), pp. 91-99.
[38]	[38]ASTM C109, Strength test method for compressive strength of hydraulic cement mortars, (2007).
[39]	Ramachandran V. S. “Thermal Analysis, in; Handbook of analytical techniques in concrete science and technology” Ramachandran V. S. and Beaudoin J. J. Eds., Noyes publications, New Jersey. ISBN: 0-8155; (2001), PP. 1473-1479.
[40]	Errington R. J. “Advanced practical inorganic and metalorganic chemistry” Blackie Academic & Professional, An Imprint Chapman & Hall; (1997).
[41]	Sobolev K., et al. “Engineering of SiO₂ nano-particles for optimal performance in nano cement-based materials” Editors: Bittnar Z., Bartos P. J. M., Nemecek J., Smilauer V., Zeman J. Nanotechnology in Construction: Proceedings of the NICOM₃ Prague; (2009), pp. 139–48.
[42]	Bjornstrom J., Martinelli A., Matic A., Borjesson L. and Panas I. “Accelerating effects of colloidal nanosilica for beneficial calcium–silicate–hydrate formation in cement” Chemical Physic Letter, 392, (2004), pp. 242 – 248.
[43]	Qing Y., Zenan Z. H., Deyu K. and Rongshen C. H. “Influence of nano-SiO₂ addition on properties of hardened cement paste as compared with silica fume”. Construction and Building Materials, 21, (2007), pp. 539–545.
[44]	Li G. “Properties of high volume fly ash concrete incorporating nano SiO₂” Cem. Concr. Res. 34, (2004), pp. 1043–1049.
[45]	Abd El. Aziz M., Abd El Aleem S., Heikal M., El. Didamony H. “Effect of Polycarboxylate on Rice Husk Ash Pozzolanic Cement” Sil. Ind., 69, 9-10; (2004), pp. 73-84.
[46]	Legrand C, Wirquin E. “Study of the strength of very young concrete as a function of the amount of hydrates formed-influence of superplasticizer” Mater. Struct.; 166, (1994), pp. 106–9.
[47]	Li H, Zhang M, Ou J. “Flexural fatigue performance of concrete containing nanoparticles for pavement”. Int. J. Fatigue; 29, (2007), pp. 1292–301.
[48]	Bensted J., Applications of Infrared Spectroscopy to cement hydration, paper delivered at the Construction Materials Group and Institute of Materials Meeting on Techniques for Characterization of cement hydration, London (1994) Society of Chemical Industry.
[49]	Gao X. F., Lo Y., Tam C. M. and Chung C. Y., "Analysis of the infrared spectrum and microstructure of hardened cement paste", Cem. Concr. Res., 29, (1999), pp. 805-812.
[50]	Delgado A. H., Paroli R. M. and Beaudoin J. J., Comparison of IR techniques for the characterization of construction cement minerals and hydrated products, Applied Spectroscopy, 50(8); (1996), pp. 970-976.
[51]	Lee, Chemistry of cement and concert London Arnold Ltd (2007).
[52]	Ghabezloo Siavash, Sulem Jean, Saint-Marc Jérémie. The effect of undrained heating on a fluid-saturated hardened cement paste. Cem Concr Res. 2009; 39: 54–64.
[53]	Zhongwei W, Huizhen L. High Performance Concrete. Beijing: China Railway Publishing Company; 1999. p. 49–50.
[54]	Xin W, Xunyan T, Yansheng Y, Yu Z. Analysis on Toughening Mechanisms of Ceramic Nano-Composites. J Ceram 2000; 2: 107–11. in Chinese.
[55]	Xijun W, Mingwen Z. Properties and Interfacial Microstructures for Nanostructured Materials. Chin J Atomic Mol Phys 1997; 2: 148–52. in Chinese.

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Hamdy El-Didamony Ahmed, Berry Abd El-Ghani Sabrah, Saleh Abd El-Aleem Mohamed, Nashwa Mohamed Mostafa. (2017). Chemical and Engineering Properties of Blended Cement Containing Micro- and Nano-silica. American Journal of Chemical Engineering, 5(5), 111-121. https://doi.org/10.11648/j.ajche.20170505.13

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ACS Style

Hamdy El-Didamony Ahmed; Berry Abd El-Ghani Sabrah; Saleh Abd El-Aleem Mohamed; Nashwa Mohamed Mostafa. Chemical and Engineering Properties of Blended Cement Containing Micro- and Nano-silica. Am. J. Chem. Eng. 2017, 5(5), 111-121. doi: 10.11648/j.ajche.20170505.13

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AMA Style

Hamdy El-Didamony Ahmed, Berry Abd El-Ghani Sabrah, Saleh Abd El-Aleem Mohamed, Nashwa Mohamed Mostafa. Chemical and Engineering Properties of Blended Cement Containing Micro- and Nano-silica. Am J Chem Eng. 2017;5(5):111-121. doi: 10.11648/j.ajche.20170505.13

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@article{10.11648/j.ajche.20170505.13,
  author = {Hamdy El-Didamony Ahmed and Berry Abd El-Ghani Sabrah and Saleh Abd El-Aleem Mohamed and Nashwa Mohamed Mostafa},
  title = {Chemical and Engineering Properties of Blended Cement Containing Micro- and Nano-silica},
  journal = {American Journal of Chemical Engineering},
  volume = {5},
  number = {5},
  pages = {111-121},
  doi = {10.11648/j.ajche.20170505.13},
  url = {https://doi.org/10.11648/j.ajche.20170505.13},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajche.20170505.13},
  abstract = {Nano-technology (NT) and nano-materials (NMs) has attracted considerable scientific attention, due to the new potential uses of nano-particles (NPs), which can change the concrete world. There is a great interest in replacing a long time used materials in concrete structure by NMs to improve the different properties of concrete. In this study, the hydration characteristics and microstructure of cement pastes and mortars with and without nano-silica (NS) were studied. Blended cement mix containing 10 mass, % silica fume (SF) was prepared, then the cement mix was partially replaced by NS up 1.5 mass, %. The results show that, NS increases the water of consistency and final setting time The values of chemically combined water, free lime, bulk density and compressive strength prove that, NS up to 1% seems to be an effective mineral additive for blending with OPC to improve its chemical and engineering properties. This is mainly attributed to that; NS behaves not only as filler to improve microstructure, but also as pozzolanic material (PZM). The formation of more hydrated silicates in presence of NS was confirmed by XRD, DTA, IR and SEM examinations. At 1.5 mass, % NS, the density and strength are reduced but still higher than those of 0.0 and 0.5% NS. Also, the results indicate that, the substitution of blended cement mix (OPC+10% SF) with 1 mass, % NS gives a reasonable hydration characteristics and improved engineering properties more than those of 0.0 and 0.5% NS at all hydration ages up to 90 days. Therefore, this level of NS is suggested to be the most suitable replacement level.},
 year = {2017}
}

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TY  - JOUR
T1  - Chemical and Engineering Properties of Blended Cement Containing Micro- and Nano-silica
AU  - Hamdy El-Didamony Ahmed
AU  - Berry Abd El-Ghani Sabrah
AU  - Saleh Abd El-Aleem Mohamed
AU  - Nashwa Mohamed Mostafa
Y1  - 2017/11/03
PY  - 2017
N1  - https://doi.org/10.11648/j.ajche.20170505.13
DO  - 10.11648/j.ajche.20170505.13
T2  - American Journal of Chemical Engineering
JF  - American Journal of Chemical Engineering
JO  - American Journal of Chemical Engineering
SP  - 111
EP  - 121
PB  - Science Publishing Group
SN  - 2330-8613
UR  - https://doi.org/10.11648/j.ajche.20170505.13
AB  - Nano-technology (NT) and nano-materials (NMs) has attracted considerable scientific attention, due to the new potential uses of nano-particles (NPs), which can change the concrete world. There is a great interest in replacing a long time used materials in concrete structure by NMs to improve the different properties of concrete. In this study, the hydration characteristics and microstructure of cement pastes and mortars with and without nano-silica (NS) were studied. Blended cement mix containing 10 mass, % silica fume (SF) was prepared, then the cement mix was partially replaced by NS up 1.5 mass, %. The results show that, NS increases the water of consistency and final setting time The values of chemically combined water, free lime, bulk density and compressive strength prove that, NS up to 1% seems to be an effective mineral additive for blending with OPC to improve its chemical and engineering properties. This is mainly attributed to that; NS behaves not only as filler to improve microstructure, but also as pozzolanic material (PZM). The formation of more hydrated silicates in presence of NS was confirmed by XRD, DTA, IR and SEM examinations. At 1.5 mass, % NS, the density and strength are reduced but still higher than those of 0.0 and 0.5% NS. Also, the results indicate that, the substitution of blended cement mix (OPC+10% SF) with 1 mass, % NS gives a reasonable hydration characteristics and improved engineering properties more than those of 0.0 and 0.5% NS at all hydration ages up to 90 days. Therefore, this level of NS is suggested to be the most suitable replacement level.
VL  - 5
IS  - 5
ER  -

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Author Information

Hamdy El-Didamony Ahmed

Chemistry Department, Faculty of Science, Zagazig University, Zagazig, Egypt
Berry Abd El-Ghani Sabrah

Chemistry Department, Faculty of Science, Fayoum University, Fayoum, Egypt
Saleh Abd El-Aleem Mohamed

Chemistry Department, Faculty of Science, Fayoum University, Fayoum, Egypt
Nashwa Mohamed Mostafa

Faculty of Science, Fayoum University, Fayoum, Egypt

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Hamdy El-Didamony Ahmed, Berry Abd El-Ghani Sabrah, Saleh Abd El-Aleem Mohamed, Nashwa Mohamed Mostafa. (2017). Chemical and Engineering Properties of Blended Cement Containing Micro- and Nano-silica. American Journal of Chemical Engineering, 5(5), 111-121. https://doi.org/10.11648/j.ajche.20170505.13

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ACS Style

Hamdy El-Didamony Ahmed; Berry Abd El-Ghani Sabrah; Saleh Abd El-Aleem Mohamed; Nashwa Mohamed Mostafa. Chemical and Engineering Properties of Blended Cement Containing Micro- and Nano-silica. Am. J. Chem. Eng. 2017, 5(5), 111-121. doi: 10.11648/j.ajche.20170505.13

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AMA Style

Hamdy El-Didamony Ahmed, Berry Abd El-Ghani Sabrah, Saleh Abd El-Aleem Mohamed, Nashwa Mohamed Mostafa. Chemical and Engineering Properties of Blended Cement Containing Micro- and Nano-silica. Am J Chem Eng. 2017;5(5):111-121. doi: 10.11648/j.ajche.20170505.13

Copy | Download

@article{10.11648/j.ajche.20170505.13,
  author = {Hamdy El-Didamony Ahmed and Berry Abd El-Ghani Sabrah and Saleh Abd El-Aleem Mohamed and Nashwa Mohamed Mostafa},
  title = {Chemical and Engineering Properties of Blended Cement Containing Micro- and Nano-silica},
  journal = {American Journal of Chemical Engineering},
  volume = {5},
  number = {5},
  pages = {111-121},
  doi = {10.11648/j.ajche.20170505.13},
  url = {https://doi.org/10.11648/j.ajche.20170505.13},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajche.20170505.13},
  abstract = {Nano-technology (NT) and nano-materials (NMs) has attracted considerable scientific attention, due to the new potential uses of nano-particles (NPs), which can change the concrete world. There is a great interest in replacing a long time used materials in concrete structure by NMs to improve the different properties of concrete. In this study, the hydration characteristics and microstructure of cement pastes and mortars with and without nano-silica (NS) were studied. Blended cement mix containing 10 mass, % silica fume (SF) was prepared, then the cement mix was partially replaced by NS up 1.5 mass, %. The results show that, NS increases the water of consistency and final setting time The values of chemically combined water, free lime, bulk density and compressive strength prove that, NS up to 1% seems to be an effective mineral additive for blending with OPC to improve its chemical and engineering properties. This is mainly attributed to that; NS behaves not only as filler to improve microstructure, but also as pozzolanic material (PZM). The formation of more hydrated silicates in presence of NS was confirmed by XRD, DTA, IR and SEM examinations. At 1.5 mass, % NS, the density and strength are reduced but still higher than those of 0.0 and 0.5% NS. Also, the results indicate that, the substitution of blended cement mix (OPC+10% SF) with 1 mass, % NS gives a reasonable hydration characteristics and improved engineering properties more than those of 0.0 and 0.5% NS at all hydration ages up to 90 days. Therefore, this level of NS is suggested to be the most suitable replacement level.},
 year = {2017}
}

Copy | Download

TY  - JOUR
T1  - Chemical and Engineering Properties of Blended Cement Containing Micro- and Nano-silica
AU  - Hamdy El-Didamony Ahmed
AU  - Berry Abd El-Ghani Sabrah
AU  - Saleh Abd El-Aleem Mohamed
AU  - Nashwa Mohamed Mostafa
Y1  - 2017/11/03
PY  - 2017
N1  - https://doi.org/10.11648/j.ajche.20170505.13
DO  - 10.11648/j.ajche.20170505.13
T2  - American Journal of Chemical Engineering
JF  - American Journal of Chemical Engineering
JO  - American Journal of Chemical Engineering
SP  - 111
EP  - 121
PB  - Science Publishing Group
SN  - 2330-8613
UR  - https://doi.org/10.11648/j.ajche.20170505.13
AB  - Nano-technology (NT) and nano-materials (NMs) has attracted considerable scientific attention, due to the new potential uses of nano-particles (NPs), which can change the concrete world. There is a great interest in replacing a long time used materials in concrete structure by NMs to improve the different properties of concrete. In this study, the hydration characteristics and microstructure of cement pastes and mortars with and without nano-silica (NS) were studied. Blended cement mix containing 10 mass, % silica fume (SF) was prepared, then the cement mix was partially replaced by NS up 1.5 mass, %. The results show that, NS increases the water of consistency and final setting time The values of chemically combined water, free lime, bulk density and compressive strength prove that, NS up to 1% seems to be an effective mineral additive for blending with OPC to improve its chemical and engineering properties. This is mainly attributed to that; NS behaves not only as filler to improve microstructure, but also as pozzolanic material (PZM). The formation of more hydrated silicates in presence of NS was confirmed by XRD, DTA, IR and SEM examinations. At 1.5 mass, % NS, the density and strength are reduced but still higher than those of 0.0 and 0.5% NS. Also, the results indicate that, the substitution of blended cement mix (OPC+10% SF) with 1 mass, % NS gives a reasonable hydration characteristics and improved engineering properties more than those of 0.0 and 0.5% NS at all hydration ages up to 90 days. Therefore, this level of NS is suggested to be the most suitable replacement level.
VL  - 5
IS  - 5
ER  -

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