Corrosion Potential Test is a non-destructive testing method used to assess the likelihood of corrosion activity in steel reinforcement embedded within concrete structures. It helps in identifying areas where reinforcement corrosion may be occurring or is likely to occur in the future.

Principle: The test is based on measuring the electrical potential difference between the embedded steel reinforcement and a reference electrode placed on the concrete surface. The potential value indicates the probability of active corrosion.

Equipment: A half-cell potential meter, reference electrode (commonly copper/copper sulfate electrode), connecting wires, and a voltmeter are used for this test.

Procedure:

Surface Preparation: The concrete surface is cleaned and slightly moistened to ensure good electrical contact.

Connection Setup: The reinforcement steel is electrically connected to the test instrument.

Measurement: The reference electrode is placed on the concrete surface, and potential readings are taken at regular grid points across the structure.

Data Interpretation: The measured potential values are analyzed to determine the probability of corrosion activity in different areas of the structure.

Applications:

• Identifying corrosion risk in reinforced concrete structures
• Evaluating condition of bridges, buildings, and marine structures
• Supporting maintenance, repair, and rehabilitation planning
• Monitoring deterioration in aging infrastructure

Advantages:

• Non-destructive and quick testing method
• Helps detect corrosion activity at an early stage
• Useful for mapping corrosion-prone areas in structures
• Supports decision-making for repair and maintenance

Limitations:

• Does not measure actual corrosion rate, only probability
• Accuracy affected by moisture, temperature, and concrete condition
• Requires proper interpretation and experience for reliable results