Study of corrosion products induced under different environmental conditions

Abstract

Corrosion in reinforced concrete structures is mainly governed by materials properties as well as environmental conditions. In this paper, the rust products produced under two different environmental conditions were investigated. In the first group of specimens, corrosion was induced by conducting wetting and drying cycles for about two years, whilst the other group was artificially corroded by impressed a voltage technique. Composition analysis of corrosion products assembled on steel reinforcement was carried out using X-ray diffraction (XRD), while the main elements existed in corrosion were identified via Energy-dispersive X-ray spectroscopy (EDX). The morphological characterization of tested corrosion was analysed by scanning electron microscopy (SEM). The results obtained from XRD and SEM at the same level of corrosion showed that lepidocrocite, goethite and magnetite were observed under both types of conditions, whilst akaganeite was only identified under exposure to natural conditions.