Performance Evaluation of Corroded Post-Tensioned Tendons under Structural Loading

Abstract

Prestressed concrete, particularly post-tensioned systems, is widely used in modern infrastructure due to its superior load-carrying capacity, crack control, and material efficiency. However, the long-term durability of such systems is significantly affected by corrosion of steel tendons, which remain hidden within ducts and are difficult to inspect. This study investigates the influence of corrosion on the mechanical and structural performance of post-tensioned tendons. The research focuses on understanding corrosion mechanisms, including chloride-induced corrosion, carbonation, and stress corrosion cracking, along with key influencing factors such as grouting quality, environmental exposure, and material properties. The effects of corrosion on tendon performance are evaluated in terms of loss of cross-sectional area, reduction in prestressing force, deterioration of bond strength, and decreased ductility and fatigue resistance. A comprehensive methodology involving literature review, analytical assessment, and proposed experimental investigation is adopted to establish relationships between corrosion levels and performance degradation. The study highlights that corrosion not only reduces load-carrying capacity but also increases the risk of brittle failure, posing serious safety concerns for aging infrastructure. The findings emphasize the need for improved design practices, effective corrosion protection systems, and regular monitoring strategies. The outcomes of this research provide a basis for predicting residual life, planning maintenance, and enhancing the durability and reliability of post-tensioned concrete structures.

Introduction

Prestressed concrete is widely used in modern structural engineering because it improves the weakness of normal concrete in tension. Prestressing introduces compressive forces into concrete using high-strength steel tendons, reducing cracking, increasing durability, and improving load-carrying capacity. In post-tensioned systems, steel wires, strands, or bars are tensioned after concrete gains strength, and ducts are grouted to protect against corrosion and maintain structural integrity.

However, the long-term performance of prestressed concrete depends on material quality, construction practices, and environmental conditions. Several failures, especially in Germany, have been linked to stress corrosion cracking (SCC) and hydrogen-induced stress corrosion cracking (H-SCC) of prestressing steel. H-SCC occurs when three conditions exist: susceptible steel, tensile stress, and a corrosive environment. Hydrogen generated during corrosion enters the steel, causing microcracks that can grow and lead to brittle fracture.

Although concrete normally protects steel through its alkaline environment, problems such as carbonation, chloride penetration, and moisture exposure can cause corrosion, pitting, and hydrogen accumulation. Therefore, understanding material behavior, environmental effects, and construction quality is essential for preventing failures.

Prestressing steel is manufactured from high-carbon steel and achieves high strength through:

• Chemical composition: High carbon and manganese content with controlled alloying elements such as chromium and vanadium to improve strength.
• Thermal treatment: Processes such as lead patenting and the modern Stelmore process create a fine pearlitic structure suitable for high-strength wire production.
• Cold working: Deformation strengthening during wire drawing increases tensile strength.

Experimental investigations showed that corrosion mainly developed in crevice regions between steel wires rather than on exposed surfaces. Severe crevice corrosion caused section loss, surface cracks, and possible wire failure. In bundled strands, corrosion concentrated along contact areas between wires.

The study indicates that prestressing steel failures are mainly caused by corrosion-related mechanisms. General corrosion can reduce steel cross-section until failure occurs, while localized corrosion such as pitting can promote hydrogen embrittlement and stress corrosion cracking. Experimental results confirmed the development of hydrogen-induced cracks under aggressive acidic conditions, although severe acid attack remained the primary cause of damage in the tested steel.

Conclusion

The results shown in the paper suggested that crevice condition, that can easily occur in restressing steel in concrete construction due to execution faults or construction errors, may lead to severe corrosion attack. Crevice can also occur in chloride contaminated concrete on inner wire surface of wire strands. Hydrogen induced cracks can develop in such condition on steel wire. On the basis of the results here reported it was however still difficult to evaluate the influence of such cracks on the failure of restressing steel.

References

[1] laee, P., & Clark, A. (2015). Evaluation of corrosion in post-tensioned tendons using non-destructive testing methods. Construction and Building Materials, 92, 105–116. https://doi.org/10.1016/j.conbuildmat.2015.03.061 [2] Berke, N. S., & Hicks, M. C. (2004). Corrosion protection of post-tensioned tendons. PCI Journal, 49(1), 68–75. [3] Byrne, D., & O’Connor, A. (2018). Assessment of the durability of post-tensioned bridges under corrosive environments. Engineering Structures, 160, 250–262. [4] Dang, Y., & Francois, R. (2014). Accelerated corrosion test of post-tensioned tendons: Performance assessment and modeling. Cement and Concrete Research, 65, 74–84 [5] El?Hacha, R., & Rizkalla, S. H. (2002). Durability of post-tensioned concrete members with unbonded tendons subjected to corrosion. ACI Structural Journal, 99(4), 455–463. [6] Freyermuth, C. L. (1998). Corrosion of prestressing steels and its prevention. PCI Journal, 43(6), 52–63. [7] Huo, X., Stewart, M. G., & Mullard, J. (2010). Concrete bridge corrosion damage analysis incorporating corrosion-induced prestress losses. Engineering Structures, 32(3), 720–731. [8] Martin, R. P., & Hamilton, H. R. (2016). Performance of post-tensioned bridges affected by grout voids and corrosion. Journal of Bridge Engineering, 21(12), 04016093. [9] Post-Tensioning Institute (PTI). (2018). Recommendations for Stay Cable Design, Testing and Installation (PTI DC35.1-18). Post-Tensioning Institute, Phoenix, AZ. [10] Rani, A., & Singh, J. (2017). Corrosion damage and service life prediction of post-tensioned concrete systems. Journal of Materials in Civil Engineering, 29(7), 04017028. [11] Rosenberg, A., & Gaidis, J. M. (2002). Corrosion of prestressed tendons in grouted ducts – A state-of-the-art review. Cement and Concrete Composites, 24(1), 37–44. [12] Tang, F., & Chen, G. (2019). Corrosion-induced deterioration and residual capacity of post-tensioned concrete girders. Engineering Failure Analysis, 104, 859–872. [13] Tang, F., & Chen, G. (2017). Inspection and evaluation of corrosion-affected post-tensioned bridges. Journal of Performance of Constructed Facilities, 31(3), 04016102. [14] Tran, N. H., & Stewart, M. G. (2015). Service life prediction for post-tensioned concrete bridges under chloride attack. Structure and Infrastructure Engineering, 11(11), 1458–1472 [15] Woodward, R. J., & Williams, J. M. (1992). Investigation of corrosion problems in post-tensioned concrete bridges. Construction and Building Materials, 6(4), 221–228. [16] Xiao, J., Li, Z., & Sun, Z. (2019). Corrosion monitoring and evaluation in post-tensioned systems using acoustic emission techniques. Sensors, 19(14), 3178. [17] Yang, L., & Liu, Y. (2020). Experimental investigation of corrosion damage in bonded post-tensioned concrete beams. Construction and Building Materials, 247, 118615. [18] Yehia, S., Abudayyeh, O., & Nabulsi, S. (2008). Assessment of bridge post-tensioned tendons using ground-penetrating radar. NDT & E International, 41(8), 589–597. [19] Zhang, T., & Song, G. (2021). Corrosion detection and structural health monitoring of prestressing steel strands in post-tensioned concrete beams using guided waves. Sensors and Actuators A: Physical, 317, 112483. [20] Zhu, W., & Wang, Z. (2022). Numerical modeling of corrosion propagation in post-tensioned tendon ducts. Engineering Structures, 259, 114145. [21] Additional Useful Codes and Standards [22] IS 1343:2012 – Code of Practice for Prestressed Concrete [23] ASTM G1-03 (2017) – Standard Practice for Preparing, Cleaning, and Evaluating Corrosion Test Specimens [24] ACI 222R-19 – Protection of Metals in Concrete Against Corrosion [25] PTI M50.3-19 – Field Procedures for Grouting Post-Tensioned Structures [26] EN 1992-2 (Eurocode 2) – Design of Concrete Structures – Bridges. [27] Andrade, C., & Alonso, C. (2001). Corrosion rate monitoring in the laboratory and on-site. Construction and Building Materials, 15(2–3), 79–90. https://doi.org/10.1016/S0950-0618(00)00063-6 [28] Apostolopoulos, C. A., & Papadakis, V. G. (2008). Consequences of steel corrosion on the ductility properties of reinforcement bar. Construction and Building Materials, 22(12), 2316–2324. [29] Broomfield, J. P. (2007). Corrosion of Steel in Concrete: Understanding, Investigation, and Repair. Taylor & Francis, London. [30] Cairns, J., & Plizzari, G. A. (2011). Structural implications of corrosion damage in prestressed concrete tendons. Magazine of Concrete Research, 63(6), 447–456.

Copyright

Copyright © 2026 Tambe Vaibhav Vasant, Prof. Hemant D. Wagh, Dr. D. M. Patel. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.