Study On Experiment Of Bending Load Rc Members Under Chloride Environment And Corrosion Of Steel Bar In The Tidal Zone

Chloride ion penetration is one of the important factors that influences the durability of RC members. RC structures are serviced with loads and environment. Microcracks caused by loads will affect the chloride ion penetration in concrete. When critical chloride concentration is reached in rebar surface, corrosion process will be in progress, and then the bearing capacity of RC members and safety of structures will decreased.In present study, the test method of chloride ion ingress in concrete with different environment condition of natural tidal zone exposure, salt fog and dry-wet cycling environment in artificial simulation environment were designed. The influences of bending loads, time, cement-water ratio and environment factors on the chloridle diffusivity were studyed. The variety of bearing capacity, rebar corrosion and mechanical property of RC members were discussed. On the basis of similarity theory, the main factors of chloride penetration in different environment conditions were analyzed. The main contents are as follows:1. The performance of resistance to chloride ion erosion of RC beams with bending loads were studied in the tidal zone under marine environment.The influences of bending loads, erosion time,cement-water ratio and environmental factors on free chloride concentration and diffusion coefficients in concrete have been studied.2. Based on the accelerated simulation experiment under the artificial climate salt fog environment and the artificial climate dry-wet cycling environment, the influence of water cement ratio, bending loads and exposure time on the main parameters of chloride ingress involving the free chloride ions concentration and diffusion coefficients were studied, and these time-dependent laws about chloride diffusion coefficient and chloride concentration were also analyzed.3. The deterioration of structural behavior such as bearing capacity, failure mode and rebar corrosion under the different chloride ion erosion environment were studied. The decreases of bearing capacity and the effect of exposure time on corrosion ratio were also studied.4. On the basis of the present research and similarity theory, the simulation of chloride ion erosion process, the diffusion properties of chloride in concrete and bearing capacity degradation of RC members under the marine environment are analyzed, artificial climate salt fog environment and artificial climate dry-wet cycling environment.