Study on Degradation Law and Related Mechanism of Mechanical Properties of Internal Reinforcement of RC Bridge After Uneven Corrosion

In order to explore the corrosion process of the internal reinforcement of the bridge under the actual working conditions. In this paper, the accelerated stress corrosion test of HRB400e steel bar was carried out by full immersion method in laboratory, and the constant tensile stress was applied to the experimental steel bar in the form of constant moment beam specimen. After the test, the mechanical properties and microstructure of the steel bar were tested, and the experimental model was analyzed by finite element simulation. The experimental results show that with the increase of load, the corrosion degree of reinforcement increases gradually, and the number of pitting holes increases obviously. Microcracks lead to transgranular failure of metal lattice, which makes the microstructure more loose. The mechanical properties of steel bar have different degrees of degradation after rust, and the degradation of elongation is the most obvious. The results of finite element simulation are similar to the actual experiment, and there are obvious pitting pits at the stress concentration.