Ikotun B.D.
University of South Africa, South Africa
Title: General Overview of the Effect of FA-β-CD composite on concrete behaviour
Biography
Biography: Ikotun B.D.
Abstract
This study looked into the possibility of increasing the utilisation of fly ash (FA) in concrete technology. FA, being an industrial waste that is in abundance in South Africa and a source of environmental pollution is presently being used minimally in the construction industry. The study on its interaction with cyclodextrin (an enzymatic modification of starch) for possible increased usage in concrete operations was done. Different South African fly ashes were characterised and their compatibility with cyclodextrin to form a useful composite was studied by XRD, SEM and FT-IR. Composite samples were synthesized following two different procedures. Since these are novel composites, indicative tests were performed on strength (compressive and split tensile) and durability (oxygen permeability, sorptivity and porosity) on mortar/concrete made with FA (30% of cement by mass) and fly ash-β-cyclodextrin (FA-β-CD) composite, that further guided the research. Based on the indicative tests results, a possible optimum composite synthesis method and percentages of β-cyclodextrin (β-CD) in the mixtures were identified. These optimal parameters were used to study the effect of FA, β-CD and (FA-β-CD) composite on cement paste hydration (XRD, SEM and FT-IR), rheology (viscosity and setting time), concrete strength (compressive and split tensile) and concrete durability (oxygen permeability, sorptivity, porosity and chloride conductivity). In general, concrete’s hydration products were modified with FA–cyclodextrin composite, which boosted the performance of FA in concrete. The composite improved FA concrete’s early compressive strength, permeability, sorptivity, porosity and chloride conductivity.