Electrical survey techniques for corrosion assessment in steel structures: case studies, equipment analysis, and practical applications

Abstract

Introduction: the corrosion of steel structural components is one of the key pathologies at the level of civil engineering since it represents serious risks to the resistance and life of infrastructures. Objectives: this research aims to investigate the practical effectiveness of electrical surveys as a non-destructive technique for the diagnosis of corrosion of metal structures, especially in environments where the system becomes highly susceptible, such as bridges, tanks, pipes, and reinforced concrete elements. Methodology: the study was conducted through a systematic review of case studies and comparing experimental data with different survey configurations (Wenner, Schlumberger, dipole-dipole). Results: an analysis of electrical resistivity was conducted by environmental variables (humidity, salinity, chloride content), descriptive statistics and correlational analysis. The study found that 85% of the cases, with resistivity <100 Ω·m, presented conditions that were likely to be active corrosion. Similarly, we found an inverse correlation (r = -0.73) between resistivity and structural deterioration. The results indicated that the accuracy used was better in homogeneous soils, although it was also shown to fail in heterogeneous environments. Conclusions: it is suggested that electrical surveys can be an effective instrument to establish risk areas, however, if they are combined with techniques such as half-cell potential or impedance spectroscopy. This method allows for the development of planned maintenance plans, and this optimization of resources can improve and extend the life of the infrastructure. General area of study: Civil Engineering. Specific area of study: Metal structure. Type of article: bibliographic review.