Use and effect of fly ash in concrete: A literature review

Concrete production is characterized by a significant demand for energy and raw materials. The construction, maintenance, and demolition of engineering works cause excessive polluting waste that requires costly disposal. For this reason, alternative reusable materials that improve the mechanical properties of concrete, such as fly ash, are currently being investigated as an effective solution to reduce problems related to environmental impact. This paper analyzed 80 articles indexed in different databases such as ScienceDirect, IOPscience, Scielo, Ebsco, Scopus, SpringerLink, ProQuest, Dialnet, and Semanticscholar, which were not older than seven years since publication, to conduct an updated systematic review of the use, effect, and influence of fly ash on concrete. The methodologies and designs used to obtain the optimum percentages of 5, 10, and 15% were reviewed, analyzing mainly the results obtained when fly ash is used in concrete. Finally, according to the review carried out, it was concluded that fly ashes improve the mechanical and physical characteristics of concrete, and that the optimum dosage is 10% in substitution of ordinary Portland cement applied in simple concrete.