Strength Improvement and Mixing Water Reduction of Combined use of Fly Ash and a Generic Naphthalene Based Superplasticizer in Concrete
Authors: Adinna, B.O., Okonkwo, V.O. And Uzodinma, F.C.
DOI Info: http://doi.org/10.5281/zenodo.8094667
ABSTRACT
Among the most important properties of a concrete are its workability, strength and durability. These properties ordinarily are achieved by varying the grading of aggregates and proportions of the basic concrete components. Today, admixtures have taken over because they are easier to apply and are also more effective. However, the technology and availability of admixture is not easily assured, especially in developing countries. This work is concerned with the use of a combination of fly ash and a generic sulfonated naphthalene-formaldehyde (SNF) condensate superplasticizer to show the water reducing, workability and strength enhancement potentials of their combination. A grade 20 concrete of nominal mix proportion of 1:2:4 and an initial water-cement ratio (w/c) of 0.6 was used; and a constant consistency of 50 mm slump maintained throughout the experiment. The variation of the strength of the concrete and the water-cement ratio (w/c) was studied as the various combined quantities of superplasticizer and fly ash was added. It was observed that the 28-days strength of the concrete increased with increase in either fly ash or superplasticizer in the combination. The strength obtained was much higher than that of the control mix. The water-cement ratio also reduced in the same order, showing more reduction than using fly ash or SNF superplasticizer alone. This showed that there is a great advantage in the combined use of both admixtures.
Affiliations: Department of Civil Engineering, Nnamdi Azikiwe University Awka, Awka, Nigeria.
Keywords: Concrete, Workability, Strength, Consistency, Mixing Water Reduction, Fly Ash, Generic Superplasticizer
Published date: 2023/06/30
