How does corrosion affect the strength of a high-strength steel cable in a suspension bridge?

Corrosion reduces the strength of a high-strength steel cable in a suspension bridge by decreasing its effective cross-sectional area and introducing stress concentrations. As corrosion occurs, the steel is converted into rust, which is weaker and less dense than the original steel. This reduces the amount of steel available to carry the tensile loads, directly reducing the cable's load-carrying capacity. Furthermore, corrosion creates pits and irregularities on the surface of the cable, which act as stress concentrators. These stress concentrations can significantly increase the stress levels in the remaining steel, making it more susceptible to fatigue and fracture. Even a small amount of corrosion can significantly weaken a high-strength steel cable, jeopardizing the overall stability of the suspension bridge.