Post-tensioned (PT) concrete bridges are valued for their efficiency, rapid construction, and aesthetic appeal, but their long-term performance is often constrained by corrosion of internal and external tendons, which serve as the primary load-carrying components. Corrosion-related tendon failures have raised significant safety concerns internationally. This paper reviews the sources of tendon corrosion, current detection technologies, and deterioration modeling approaches, emphasizing the challenges of inspecting protected or difficult-to-access tension elements. Field investigations show that chloride intrusion, moisture exposure, inadequate grout quality, damaged ducts or anchorages, and construction deficiencies frequently initiate tendon deterioration. These issues can result in barrier degradation, wire corrosion, grout voids, anchorage distress, strand rupture, and associated concrete damage. Due to limited access, nondestructive testing methods play a critical role in assessing conditions. The paper also underscores the need for probabilistic life-cycle models that incorporate inspection data to quantify uncertainty, predict remaining tendon capacity, and guide timely maintenance planning.
