journal article Open Access Aug 12, 2025

Investigating the synergistic effects of Metakaolin and silica fume on the strength and durability of recycled aggregate concrete at elevated temperatures

View at Publisher Save 10.1038/s41598-025-11494-w
Abstract
Abstract
The use of recycled aggregate (RA) as a partial or full replacement of natural aggregate (NA) is a suitable method of concrete production that has positive impacts on the environment. However, recycled aggregate concrete (RAC) has relatively lower strength and durability than that of normal concrete. To improve concrete performance, silica-fume (SF) was added with 2.5% increment up to 7.5% and metakaolin (MK) is added with a 2.5% decrement from 15 to 7.5%. The concrete with 50% RA, 10% MK and 5% SF showed notable advancement in performance after 28 days of curing. At 28 days of curing, the concrete samples had 31.5 MPa compressive strength, 5.7 MPa splitting tensile strength, and 10.6 MPa flexural strength, a strength improvement of 5.19%, 16.47%, and 8.52% over control concrete. Ultrasonic pulse velocity (UPV) indicated a 16.13% increase alongside a 20.87% reduction in water absorption which confirmed stronger bond performance and better durability of modified concrete. RCA content influences acid resistance negatively when reaching 75% RCA shows maximum deterioration. In addition, the fire resistance of such concrete resulted in higher performance at different temperature conditions for the concrete. This is due to the small particles of silica fume and metakaolin which acted as major factors and led to performance enhancements by filling in the concrete matrix gaps. The combination provides affordable, sustainable construction alternatives. Experiments show that SCMs can produce high-performance recycled concrete for modern building construction.
Topics

No keywords indexed for this article. Browse by subject →

References
58
[1]
Ascensão, G., Marchi, M., Segata, M., Faleschini, F. & Pontikes, Y. Reaction kinetics and structural analysis of alkali activated Fe–Si–Ca rich materials. J. Clean. Prod. 246 https://doi.org/10.1016/j.jclepro.2019.119065 (2020). 10.1016/j.jclepro.2019.119065
[2]
Yakovlev, G. et al. Influence of sulphate attack on properties of modified cement composites. Appl. Sci. (Switzerland). 11 (18). https://doi.org/10.3390/app11188509 (2021). 10.3390/app11188509
[3]
Gonzalez-Corominas, A. & Etxeberria, M. Effects of using recycled concrete aggregates on the shrinkage of high performance concrete. Constr. Build. Mater. 115, 32–41. https://doi.org/10.1016/j.conbuildmat.2016.04.031 (2016). 10.1016/j.conbuildmat.2016.04.031
[4]
S. C. & Bostanci Use of waste marble dust and recycled glass for sustainable concrete production. J. Clean. Prod. 251 https://doi.org/10.1016/j.jclepro.2019.119785 (2020). 10.1016/j.jclepro.2019.119785
[5]
Alexandridou, C., Angelopoulos, G. N. & Coutelieris, F. A. Mechanical and durability performance of concrete produced with recycled aggregates from Greek construction and demolition waste plants. J. Clean. Prod. 176, 745–757. https://doi.org/10.1016/j.jclepro.2017.12.081 (2018). 10.1016/j.jclepro.2017.12.081
[6]
Bheel, N. et al. Fresh and mechanical properties of concrete made of binary substitution of millet husk ash and wheat straw ash for cement and fine aggregate, J. Mater. Res. Technol. 13, 872–893. (2021). https://doi.org/10.1016/j.jmrt.2021.04.095 10.1016/j.jmrt.2021.04.095
[7]
Lotfi, S., Eggimann, M., Wagner, E., Mróz, R. & Deja, J. Performance of recycled aggregate concrete based on a new concrete recycling technology. Constr. Build. Mater. 95, 243–256. https://doi.org/10.1016/j.conbuildmat.2015.07.021 (2015). 10.1016/j.conbuildmat.2015.07.021
[8]
Mohammadi, A. & Ramezanianpour, A. M. Investigating the environmental and economic impacts of using supplementary cementitious materials (SCMs) using the life cycle approach. J. Building Eng. 79, 107934. https://doi.org/10.1016/J.JOBE.2023.107934 (2023). 10.1016/j.jobe.2023.107934
[9]
Cyr, M. Influence of supplementary cementitious materials (SCMs) on concrete durability. Eco-Efficient Concrete. 153–197. https://doi.org/10.1533/9780857098993.2.153 (2013). 10.1533/9780857098993.2.153
[10]
Amjadi, R., Monazami, M., Mohseni, E., Azar Balgouri, H. & Ranjbar, M. M. Effectiveness of different recycled materials in self-compacting mortar, European Journal of Environmental and Civil Engineering 21(12), 1485–1501. https://doi.org/10.1080/19648189.2016.1175974 (2017). 10.1080/19648189.2016.1175974
[11]
Ahmad, J., Zaid, O., Pérez, C. L. C., Martínez-García, R. & López-Gayarre, F. Experimental research on mechanical and permeability properties of nylon Fiber reinforced recycled aggregate concrete with mineral admixture. Appl. Sci. (Switzerland). 12 (2). https://doi.org/10.3390/app12020554 (Jan. 2022). 10.3390/app12020554
[12]
Smirnova, O. M., de Navascués, I. M. P., Mikhailevskii, V. R., Kolosov, O. I. & Skolota, N. S. Sound-absorbing composites with rubber crumb from used tires. Appl. Sci. (Switzerland). 11 (16). https://doi.org/10.3390/app11167347 (Aug. 2021). 10.3390/app11167347
[13]
Smirnova, O. M. (2020). Low-clinker cements with low water demand. Journal of Materials in Civil Engineering, 32(7), 06020008, https://doi.org/10.1061/(ASCE)ME.1943-5479.0001005 10.1061/(asce)mt.1943-5533.0003241
[14]
Kou, S. C. & Poon, C. S. Enhancing the durability properties of concrete prepared with coarse recycled aggregate. Constr. Build. Mater. 35, 69–76. https://doi.org/10.1016/j.conbuildmat.2012.02.032 (Oct. 2012). 10.1016/j.conbuildmat.2012.02.032
[15]
Althoey, F. & Hosen, M. A. Physical and mechanical characteristics of sustainable concrete comprising industrial waste materials as a replacement of conventional aggregate, Sustainability (Switzerland) 13 (8), https://doi.org/10.3390/su13084306 (2021). 10.3390/su13084306
[16]
de Andrade Salgado, F. & de Andrade Silva, F. Recycled aggregates from construction and demolition waste towards an application on structural concrete: A review. J. Building Eng. 52, 104452. https://doi.org/10.1016/J.JOBE.2022.104452 (2022). 10.1016/j.jobe.2022.104452
[17]
Compressive and Thermal Properties of Non-Structural Lightweight Concrete Containing Industrial Byproduct Aggregates

Ilenia Farina, Ivan Moccia, Cinzia Salzano et al.

Materials 10.3390/ma15114029
[18]
Chu, S. H., Poon, C. S., Lam, C. S. & Li, L. Effect of natural and recycled aggregate packing on properties of concrete blocks. Constr. Build. Mater. 278 https://doi.org/10.1016/j.conbuildmat.2021.122247 (2021). 10.1016/j.conbuildmat.2021.122247
[19]
Berndt, M. L. Properties of sustainable concrete containing fly ash, slag and recycled concrete aggregate, Constr. Build. Mater. 23(7), 2606–2613. https://doi.org/10.1016/j.conbuildmat.2009.02.011 (2009). 10.1016/j.conbuildmat.2009.02.011
[20]
Devi, S. V., Gausikan, R., Chithambaranathan, S. & Jeffrey, J. W. Utilization of recycled aggregate of construction and demolition waste as a sustainable material, in Materials Today: Proceedings, Elsevier Ltd, pp. 6649–6654. (2020). https://doi.org/10.1016/j.matpr.2020.12.013 10.1016/j.matpr.2020.12.013
[21]
Use of recycled concrete aggregate in fly-ash concrete

Mukesh Limbachiya, Mohammed Seddik Meddah, Youssef Ouchagour

Construction and Building Materials 10.1016/j.conbuildmat.2011.07.023
[22]
Ahmad, J. et al. A study on mechanical and durability aspects of concrete modified with steel fibers (SFS), Civil Engineering and Architecture 8 (5), 814–823. https://doi.org/10.13189/cea.2020.080508 (2020). 10.13189/cea.2020.080508
[23]
Xiao, J., Zhang, Q., Zhang, P., Shen, L. & Qiang, C. Mechanical behavior of concrete using seawater and sea-sand with recycled coarse aggregates, Structural Concrete 20 (5), 1631–1643. https://doi.org/10.1002/suco.201900071 (2019). 10.1002/suco.201900071
[24]
Amin, M., Tayeh, B. A. & Agwa, I. S. Effect of using mineral admixtures and ceramic wastes as coarse aggregates on properties of ultrahigh-performance concrete. J. Clean. Prod. 273 https://doi.org/10.1016/j.jclepro.2020.123073 (2020). 10.1016/j.jclepro.2020.123073
[25]
Amin, M., Zeyad, A. M., Tayeh, B. A. & Saad Agwa, I. Engineering properties of self-cured normal and high strength concrete produced using polyethylene glycol and porous ceramic waste as coarse aggregate, Constr Build Mater 299, https://doi.org/10.1016/j.conbuildmat.2021.124243 (2021). 10.1016/j.conbuildmat.2021.124243
[26]
Amin, M. et al. Influence of recycled aggregates and carbon nanofibres on properties of ultra-high-performance concrete under elevated temperatures. Case Stud. Constr. Mater. 16, e01063. https://doi.org/10.1016/J.CSCM.2022.E01063 (2022). 10.1016/j.cscm.2022.e01063
[27]
O., M.-G. R., A. A. A. et al. Zaid, To determine the performance of metakaolin-based fiber-reinforced geopolymer concrete with recycled aggregates, Archive of Civil nd Mechanical Engineering 22, 114, (2022). 10.1007/s43452-022-00436-2
[28]
Sabireen et al. Mechanical performance of fiber-reinforced concrete and functionally graded concrete with natural and recycled aggregates. Ain Shams Eng. J. 14 (9), 102121. https://doi.org/10.1016/J.ASEJ.2023.102121 (2023). 10.1016/j.asej.2023.102121
[29]
Beersaerts, G., Ascensão, G. & Pontikes, Y. Modifying the pore size distribution in Fe-rich inorganic polymer mortars: an effective shrinkage mitigation strategy. Cem. Concr Res. 141 https://doi.org/10.1016/j.cemconres.2020.106330 (2021). 10.1016/j.cemconres.2020.106330
[30]
Choi, P., Yun, K. K. & Yeon, J. H. Effects of mineral admixtures and steel fiber on rheology, strength, and chloride ion penetration resistance characteristics of wet-mix shotcrete mixtures containing crushed aggregates. Constr. Build. Mater. 142, 376–384. https://doi.org/10.1016/j.conbuildmat.2017.03.093 (2017). 10.1016/j.conbuildmat.2017.03.093
[31]
Zaid, O., Martínez García, R. & Aslam, F. Influence of wheat straw Ash as partial substitute of cement on properties of High-Strength concrete incorporating graphene oxide. J. Mater. Civ. Eng. 34 https://doi.org/10.1061/(ASCE)MT.1943-5533.0004415 (2022). 10.1061/(asce)mt.1943-5533.0004415
[32]
Althoey, F. et al. Impact of sulfate activation of rice husk Ash on the performance of high strength steel fiber reinforced recycled aggregate concrete. J. Building Eng. 54, 104610. https://doi.org/10.1016/J.JOBE.2022.104610 (2022). 10.1016/j.jobe.2022.104610
[33]
Ahmad, J. et al. Characteristics of sustainable concrete with partial substitutions of glass waste as a binder material. Int. J. Concr Struct. Mater. 16 (1). https://doi.org/10.1186/s40069-022-00511-1 (2022). 10.1186/s40069-022-00511-1
[34]
Poon, C. S., Kou, S. C. & Lam, L. Compressive strength, chloride diffusivity and pore structure of high performance metakaolin and silica fume concrete, Constr. Build. Mater. 20 (10), 858–865. https://doi.org/10.1016/j.conbuildmat.2005.07.001 (2006). 10.1016/j.conbuildmat.2005.07.001
[35]
Sabir, B., Wild, S. & Bai, J. Metakaolin and calcined clays as Pozzolans for concrete: a review. Cem. Concr Compos. 23 (6), 441–454. https://doi.org/10.1016/S0958-9465(00)00092-5 (2001). 10.1016/s0958-9465(00)00092-5
[36]
Zhang, M. H. & Malhotra, V. M. Characteristics of a thermally activated alumino-silicate pozzolanic material and its use in concrete, Cem. Concr. Res. 25 (8), 1713–1725. https://doi.org/10.1016/0008-8846(95)00167-0 (1995). 10.1016/0008-8846(95)00167-0
[37]
Murat, M. Hydration reaction and hardening of calcined clays and related minerals. I. Preliminary investigation on metakaolinite. Cem. Concr Res. 13 (2), 259–266. https://doi.org/10.1016/0008-8846(83)90109-6 (1983). 10.1016/0008-8846(83)90109-6
[38]
Rate of pozzolanic reaction of metakaolin in high-performance cement pastes

C.-S Poon, L Lam, S.C Kou et al.

Cement and Concrete Research 10.1016/s0008-8846(01)00581-6
[39]
Khatib, J. M. & Wild, S. Pore size distribution of Metakaolin paste. Cem. Concr Res. 26 (10), 1545–1553. https://doi.org/10.1016/0008-8846(96)00147-0 (Oct. 1996). 10.1016/0008-8846(96)00147-0
[40]
Nixon, P. J. 37-DRC Committee ~ I Recycled concrete as an aggregate for concrete.
[41]
Hansen, T. C. Rilem Technical Committee-37-DRC Recycled aggregates and recycled aggregate concrete second state-of-the-art report developments 1945–1985.
[42]
ASTM C128-22. Standard Test Method for Relative Density (Specific Gravity) and Absorption of Fine Aggregate, ASTM International, West Conshohocken, PA, 2022, Vol. 04.02. DOI: 10.1520/C0128-22 10.1520/c0128-22
[43]
ASTM C127-24. Standard Test Method for Relative Density (Specific Gravity) and Absorption of Coarse Aggregate, ASTM International, West Conshohocken, PA, 2024, Vol. 04.02. DOI: 10.1520/C0127-24 10.1520/c0127-24
[44]
Ahmad, J. et al. To study the characteristics of concrete by using high range water reducing admixture, [Online]. (2020). Available: https://www.researchgate.net/publication/352704892
[45]
Ding, J. T. Effects of metakaolin and silica fume on properties of concrete. [Online]. Available: https://www.researchgate.net/publication/279902244
[46]
ASTM C511-21. Standard Specification for Mixing Rooms, Moist Cabinets, Moist Rooms, and Water Storage Tanks Used in the Testing of Hydraulic Cements and Concretes, ASTM International, West Conshohocken, PA, 2021, Vol. 04.01, 04.02. DOI: 10.1520/C0511-21 10.1520/c0511-21
[47]
Revilla-Cuesta, V., Ortega-López, V., Skaf, M. & Manso, J. M. Effect of fine recycled concrete aggregate on the mechanical behavior of self-compacting concrete. Constr. Build. Mater. 263, 120671. https://doi.org/10.1016/J.CONBUILDMAT.2020.120671 (2020). 10.1016/j.conbuildmat.2020.120671
[48]
Construction and demolition waste generation and properties of recycled aggregate concrete: A global perspective

Ali Akhtar, Ajit K. Sarmah

Journal of Cleaner Production 10.1016/j.jclepro.2018.03.085
[49]
Duan, Z. H. & Poon, C. S. Properties of recycled aggregate concrete made with recycled aggregates with different amounts of old adhered mortars. Mater. Des. 58, 19–29 (2014). 10.1016/j.matdes.2014.01.044
[50]
Koushkbaghi, M., Kazemi, M. J., Mosavi, H. & Mohseni, E. Acid resistance and durability properties of steel fiber-reinforced concrete incorporating rice husk Ash and recycled aggregate. Constr. Build. Mater. 202, 266–275 (2019). 10.1016/j.conbuildmat.2018.12.224

Showing 50 of 58 references

Metrics
7
Citations
58
References
Details
Published
Aug 12, 2025
Vol/Issue
15(1)
License
View
Cite This Article
Imran Haider, Muhammad Yaqub, Inamullah Inam, et al. (2025). Investigating the synergistic effects of Metakaolin and silica fume on the strength and durability of recycled aggregate concrete at elevated temperatures. Scientific Reports, 15(1). https://doi.org/10.1038/s41598-025-11494-w