Effect of corrosion on fatigue strength: the reduced exponent k2
Eurocode 2 part 1-1: Design of concrete structures 6.8.4 (5)
When the rules of § 6.8 are used to evaluate the remaining life of existing structures, or to assess the need for strengthening, once corrosion has started the stress range may be determined by reducing the stress exponent k2 for straight and bent bars (see § 6.8.4 (1) for more information).
Recommendation
The recommended value of k2 for this case of the effect of corrosion on fatigue strength is 5.