Early Detection of Reinforcement Corrosion in Concrete Structures: A Preliminary Investigation Using Non-Destructive Testing Techniques

The deterioration of civil infrastructures such as bridges, roads, and buildings poses substantial economic and safety threats. The timely identification and remediation of defects in concrete structures can mitigate costlier future repairs and prevent catastrophic failures [1], [2].While reinforced concrete is favoured for its strength and affordability, the embedded steel is vulnerable to corrosion induced by environmental exposure and ageing. Current evaluation methods only detect severe corrosion levels, providing insufficient warning for preventative action [3].Within this context, this research focuses on developing non-destructive testing techniques for the early detection of steel reinforcement corrosion. This project investigates the application of emerging technologies - ground-penetrating radar (GPR) and photogrammetry - to enable earlier corrosion identification in concrete specimens.The initial phase of the proposed research was dedicated to establishing testing capabilities and workflows to continuously monitor corrosion progression. Concrete samples with rebar were then subjected to accelerated corrosion in a controlled lab environment. Subsequently, GPR was employed to capture subsurface information related to rebar deterioration, while photogrammetry quantified 3D surface cracks and damage. The investigation data will have the potential to characterise corrosion severity versus concrete and rebar conditions to formulate new corrosion rating guidelines in the future.The outcomes of this preliminary research have the potential to facilitate shifting infrastructure maintenance from reactive to proactive strategies, potentially reducing repair costs and promoting resilience.Keywords: Concrete; Corrosion Detection; Photogrammetry; Ground Penetrating Radar; Infrastructure Maintenance References[1]     S. Ahmad, “Reinforcement corrosion in concrete structures, its monitoring and service life prediction––a review,” Cement and Concrete Composites, vol. 25, no. 4-5, pp. 459-471, 2003. [2]     T. Bachiri, A. Khamlichi and M. Bezzazi, “Detection of rebar corrosion in bridge deck by using GPR,” International Conference on Non-Destructive Evaluation of Composite Structures (NDECS 2017), vol. 191, 2018. [3]     J. E. Ramón-Zamora, J. R. Lliso-Ferrando, A. Martínez-Ibernón and J. M. Gandía-Romero, “Corrosion Assessment in Reinforced Concrete Structures by Means of Embedded Sensors and Multivariate Analysis—Part 1: Laboratory Validation,” Sensors, vol. 23, no. 21, 2023.