Synergism of blended extract of Ageratum houstonianum and Chromolaena odorata leaves on the corrosion inhibitor of reinforcing steel in concrete composite

¹ Central Department of Chemistry, Tribhuvan University, Kirtipur 44618, Kathmandu, Nepal
² Department of Chemistry, Tribhuvan M. Campus, Tribhuvan University, Tansen 32500, Palpa, Nepal

^* Corresponding author: neutan08@ygmail.com
^† Corresponding author: bhattarai_05@yahoo.com

Abstract

Corrosive degradation of reinforcing steel (RS) in concrete composite (ConC) is a significant factor contributing to the early collapse of reinforced concrete infrastructures. The degradation of the RS in ConC impacts if appropriate corrosion control efforts are not applied promptly. Plant-based green extracts have been recently used as anticorrosive materials to prevent RS corrosion. This study investigated the effectiveness of various concentrations of blended extracts from the leaves of Ageratum houstonianum and Chromolaena odorata (referred to as AHL-COL) in controlling the corrosion of reinforcing mild steel (RMS) in the ConC using a half-cell potential measurement with the help of the ASTM C876-22b standard. Performed the surface analysis using scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS) to examine the anticorrosive actions of the AHL-COL concentrations. The corrosion probability (P_corr) of the RMS in concrete beams with 500-2000 ppm AHL-COL is synergistically lowered compared with the control concrete beam or even the presence of individual plant extracts, as evidenced by shifting the corrosion potential (E_corr) to a zone where the P_corr of the RMS should be < 10%, and also supported by electron microscopic, and SEM-EDS analysis.