Recent failures of external prestressing grouted tendons: when the ducts take on water…

Abstract The article describes recent cases of tendon ruptures by corrosion and investigations carried out on some bridges in France. Several causes related to HDPE ducts have been identified such as damages during handling, threading tensioning strands, defective connection the duct anchorage, damage construction or operation, low quality material, etc. These rupture exclusively concern injected with cement grout. To our knowledge, no structure built after application 2001 circular [1] (prohibiting grout for injection external prestressing) is currently exhibiting major disorders. A warning note existing structures prestressing has updated Cerema November 2018 [2]. It diagnosis methodology based analysis documentation, thorough visual inspection, destructive nondestructive investigations. New non‐destructive techniques guided‐wave ultrasonic technique magnetic leakage field test using permanent magnets induction coils are presented. Innovative methods local repair also described. Finally, different protective devices analysed terms worker safety event a sudden failure tendon.