Study On Constitutive Model Of Corroded Reinforcement Under Cyclic Loading

The corrosion of steel in concrete usually experience reinforced concrete carbonization, corrosion, protective layer of concrete longitudinal cracking, crack development to component failure such a complex process of evolution, the corrosion of reinforcement will directly affect the applicability and safety of the structure, repeated load under the action of corroded steel bar stress-strain relationship is both a key problem of reinforced concrete structure seismic assessment, life prediction and the corresponding computer simulation analysis.In this paper, the corroded reinforced specimens were obtained by the component replacement method, through the monotonous and repeated load tests, the mechanical properties degradation process of corroded reinforcement were analyzed in detail, based on the experimental data fitting, the expression of stress-strain relationship of corroded reinforcement under cyclic loading were proposed. The main research works are as follows:1.The corroded reinforced specimens with different diameter and different corrosion degree were obtained by the component replacement method, the corrosion surface morphology features was observed carefully, measuring the quality of the specimen corrosion rate and the maximum cross section loss rate, is presented for the characterization of the steel corrosion rate.2.The experimental study on stress strain relationship of corroded reinforcement under monotonic and repeated load were carried out, effects of different degree of corrosion failure form of specimens, compared the different corrosion test stress-straincurves parts, analyzes the mechanism of reinforced the mechanical properties of corrosion degradation.3.Based on the experimental data fitting, the degradation of the mechanical properties of corroded reinforcement were provided, the constitutive model of corroded reinforcement under cyclic loading were established.