The half-cell potential test is a non-destructive method used to assess the corrosion risk of reinforcing steel (rebars) within concrete structures. This test involves measuring the electrical potential difference between a reference half-cell (usually copper/copper sulfate or silver/silver chloride) and the steel reinforcement embedded in the concrete. The readings indicate the likelihood of corrosion; more negative potentials suggest a higher probability of active corrosion, while less negative potentials imply a lower risk. The half-cell potential test helps engineers identify areas of corrosion activity, enabling targeted maintenance and ensuring the structural integrity and longevity of concrete structures.