Durability of FRP Rebar concrete structure. Corrosion resistance at room temperature is one of the greatest advantages of FRP bars relative to steel bars. In worse environmental conditions, the durability of FRP rebars concrete structure is one of the important issues to be studied when using FRP rebars to replace steel bars. In order to study the durability of concrete structures reinforced with Fiberglass rebars, Hamid Saada trnanesh et al. of the United States studied the stress relaxation of 10 mm diameter AFRP bars in air, alkaline, acidic and salt solutions at different temperatures, fatigue at room temperature and creep properties in air, alkaline, acidic and salt solutions at room temperature. The test results show that:
1) Stress Relaxation(0-50 years)
A, The stress relaxation of FRP bars increases with the increase of temperature.
B, The stress relaxation of FRP rebars in air is smaller than that in solution, and the stress relaxation in acid solution is the largest.
C, The stress relaxation of FRP rebars increases with the increase of initial prestress level.
2)Fatigue(Load cycle 3 million times):
A, When the stress range is 58-116MPa and the minimum stress is less than 50% of the ultimate tensile strength, Fiberglass bars show good fatigue resistance.
B, With the increase of stress range and minimum stress, the fatigue resistance of FRP rebars decreases.
3)Creep (Under 40% of the short-term ultimate tensile stress of fibre reinforcement under sustained loading): The creep properties of FRP rebars increased in acid solution, alkaline solution and air in turn. The test shows that the durability of FRP rebars in acid environment is poor, but better than that of steel bars.