The effect of adding nano-silica on the ultrasonic pulse velocity of geopolymer concrete

Document Type : Research Article


1 Standard Research Institute, Technical and Engineering Faculty, Construction and Mineral Department, Karaj, Iran

2 Department of Civil, Faculty of Engineering, University of Zanjan, Zanjan, Iran

3 Applied Science Center of Khorasan Razavi Municipalities, Mashhad, Iran


Nanotechnology plays an important role in the current construction industry. It has been observed that several properties of cement-based concrete are affected by different nano materials. In this study, different weight percentages of nano-silica (0, 1, 2, and 4 wt%) were used to build geopolymer specimens. The mechanical properties of the specimens were then measured, including the compressive and flexural strength. Results demonstrated that increasing the percentage of nano-silica from 0 to 4 wt% increases the compressive strength of the specimens from 50.4 to 75.2 MPa and the flexural strength from 11.4 to 26.2 MPa. Furthermore, it was observed that the ultrasonic pulse velocity was altered by increasing SiO2 (nano-silica), decreasing the ultrasonic pulse rate from 7.0 to 4.5 km.s-1.

Graphical Abstract

The effect of adding nano-silica on the ultrasonic pulse velocity of geopolymer concrete


  • Compressive strength increased with time in all samples. However, the rate of increase varied in different samples and alkalinity.
  • The sample with 4% weight of nano-silica provided the maximum strength after 90 days.
  • The increase of the nano-silica additive in geopolymer concrete improved the mechanical strength of concrete due to strengthening the concrete bonds.
  • The reduction of concrete porosity according to SEM images, it was seen that the ultrasonic pulse velocity decreased.
  • The minor increase of the amount of nano-silica improved the efficiency of the concrete proposed in this study.


[1] S. Naskar, A.K. Chakrabort, Effect of nano materials in geopolymer concrete, Persp. Sci. 8 (2016) 273-275.
[2] J. Davidovits, Properties of geopolymer cements, In Proceedings of the First International Conference on Alkaline Cements and Concretes, Scientific Research Institute on Binders and Materials, Kiev State Technical University, Kiev, Ukraine, 1994, pp. 131-149.
[3] A. Taffe, C. Maierhofer, Guidelines for NDT methods in Civil Engineering, Federal Institute for Materials Research (BAM), Berlin, Germany, 2003.
[4] A.M. Neville, J.J. Brooks, Concrete Technology, 2nd Ed., Prentice Hall, New York, 2010. 
[5] E.N. Kani, A. Allahverdi, Effects of curing time and temperature on strength development of inorganic polymeric binder based on natural pozzolan, J. Mater. Sci. 44 (2009) 3088-3097.
[6] Y. Lin, H. Changfan, C. Hsiao, Estimation of high performance concrete strength by pulse velocity, J. Chin. Inst. Eng. 20 (1997) 661-668.
[7] Y. Lin, C.-P. Lai, T. Yen, Prediction of ultrasonic pulse velocity (UPV) in concrete, Aci Mater. J. 100  (2003) 21-28.
[8] E.A. Whitehurst, Evaluation of concrete properties from sonic tests, American Concrete Institute Monograph, 2 (1966) 27.
[9] T.R. Naik, V.M. Malhotra, J.S. Popovics, The ultrasonic pulse velocity method, In:  Handbook on Nondestructive Testing of Concrete, 2nd Ed., CRC Press, 2003, pp. 8-19.
[10] B.S. Al-Nu’man, B.R. Aziz, S.A. Abdulla, S.E. Khaleel, Compressive strength formula for concrete using ultrasonic pulse velocity, Int. J. Eng. Trends Technol. 26 (2015) 8-13.
[11] P. Duxson, A. Fernández-Jiménez, J.L. Provis, G.C. Lukey, A. Palomo, J.S. van Deventer, Geopolymer technology: The current state of the art, J. Mater. Sci. 42 (2007) 2917-2933.
[12] Z. Zidi, M. Ltifi, Z. Ben Ayadi, L. El Mir, X. Nóvoa, Effect of nano-ZnO on mechanical and thermal properties of geopolymer,  J. Asian Ceram. Soc.  8 (2020) 1-9.
[13] H.M.M. Khater, Physicomechanical properties of nano-silica effect on geopolymer composites, J. Build. Mater. Struct. 3 (2016) 1-14. 
[14] P. Deb, P. Nath, P. Sarker, Properties of fly ash and slag blended geopolymer concrete cured at ambient temperature, in S. Yazdani, and A. Singh (ed), The 7th International Structural Engineering and Construction Conference, ISEC-7, Manoa, Honolulu: University of Hawaii, 2013, 571-576.
[15] Y. Tanigawa, K. Baba, H. Mori, Estimation of concrete strength by combined nondestructive testing method, Special Publication, 82 (1984) 57-76.
[16] U. Durak, O. Karahan, B. Uzal, S. İlkentapar, C.D. Atiş, Influence of nano SiO2 and nano CaCO3 particles on strength, workability, and microstructural properties of fly ash-based geopolymer, Struct. Concr. 22 (2021) E352–E367.
[17] J. Davidovits, Global warming impact on the cement and aggregates industries, World Resour. Rev. 6 (1994) 263-278.
[18] H.M. Khater, Effect of nano-silica on microstructure formation of low-cost geopolymer binder, Nanocomposites, 2 (2016) 84-97.
[19] O.A. Naniz, M. Mazloom, Effects of colloidal nano-silica on fresh and hardened properties of self-compacting lightweight concrete, J. Build. Eng. 20 (2018) 400-410.
[20] D. Adak, M. Sarkar, S. Mandal, Effect of nano-silica on strength and durability of fly ash based geopolymer mortar, Constr. Build. Mater. 70 (2014) 453-459.
[21] D. Tarangini, P. Sravana, P. Srinivasa Rao, Effect of nano silica on frost resistance of pervious concrete, Mater. Today-Proc. 51 (2021) 2185-2189.
[22] J. Davidovits, Geopolymer Chemistry and Applications, 4th Ed., Geopolymer Institute, Saint-Quentin, France, 2015.
[23] M. Karimaei, F. Dabbaghi, M. Dehestani, M. Rashidi, Estimating compressive strength of concrete containing untreated coal waste aggregates using ultrasonic pulse velocity, Materials, 14 (2021) 647.