Durability of reinforced concrete exposed to stray currents from DC-driven track systems under constant and varying voltages

Real-world conditions near a light rail system were simulated to examine the effect of stray electric currents on the corrosion of reinforced concrete and the service life of these elements. Field measurements were conducted near the track to estimate typical stray electric voltages. These voltages were then applied to concrete specimens in a controlled laboratory environment under two different conditions: variable voltage, as measured in the field, and with a constant voltage of 9 V. Two types of concrete were tested: normal-strength concrete (approximately 30 MPa) and medium-strength concrete (approximately 60 MPa). Crack times were recorded for both to assess their differences. Additionally, the effect of cover thickness on the amount of corrosion products and time of cracking was examined.