Investigation of Opuntia Ficus Indica (OFI) Corrosion Inhibiting Potential by Incorporating Fine Aggregate Scoria Gravel as an Enabler of Concrete Internal Curing

Abstract

Corrosion is a natural process that causes the gradual deterioration of metals and alloys, posessignificant challenges in Reinforced concretes. Despite ongoing efforts to develop effective corrosion mitigation methods, there is a demand for environmentally friendly solutions that are user-friendly and readily available. Opuntia ficus indica (OFI), a green corrosion inhibitor, has emerged as a promising option for preventing corrosion and addressing these needs. However, its effectiveness in the construction industry requires further investigation into passive film formation and inhibitory capacity without compromising the properties ofconcrete. This study aims to investigate the possible use of OFI as a corrosion inhibitor in concrete by incorporating fine aggregate scoria gravel, which facilitate extended hydration through the internal curing effect in concrete. The research seeks to evaluate OFI's ability to inhibit corrosion and its impact on enhancing the corrosion inhibition of the concrete system by supplying a portion of water in the concrete through the fine aggregate scoria gravel internal curing mechanism. To accomplish these goals, a range of experimental and analytical techniques were employed, such as X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), Electrochemical Impedance Spectroscopy (EIS), and Tafel plot analysis. The results demonstrate that a concrete mixture containing 30% OFI and 5% fine aggregate scoria gravel outperforms other combinations. This blend significantly reduces the corrosion current density from 2.195??A to 0.43??A andincreases the polarization resistance from 58.83??? to 89.1??? compared to the control mix. It also enhances cement hydration products, evident in XRD peaks. Additionally, OFI promotes crystallization, observed in SEM images, resulting in fewer corrosion pits on the reinforcement surface as examined under an optical microscope. This research adds to the current knowledge by identifying the potential use of OFI in concrete with an internal curing material and examines the formation of oxide hydroxide passive film at the concrete-reinforcement interface. The findings of this study have broad implications, promoting green enviroment and offering natural solutions for corrosion prevention for Reinforced concretes.