Chloride Ion Ingress Of The Bending RC Members And The Bending Capacity Of RC Corroded Members In Tidal Zone

When chloride ion penetrates from surrounding environments into the RC members serviced with loads,the corrosion process will be in progress,leading to a decrease of bearing capacity and ductility of the RC members and eventually affecting their safety.The test of chloride ingress into RC members under artificial simulation environment was proposed in this paper.The influences of longer exposure time,bending loads and cement-water ratio on the chloride diffusivity and the time-dependent laws of these main parameters have been studied.The time dependent characteristic of bearing capacity of RC members,the mechanical properties of corroded steel bars,as well as the nonuniformity of the corroded reinforcement was analyzed.The model of flexural bearing capacity of concrete beams with reinforcement under different corroded condition was built.The main contents are as follows:1.The free chloride concentration and time-dependent rules of chloride diffusivity of RC beams with bending loads were studied under the tidal marine environment.The influences of exposure time,cement-water ratio and bending loads level on the free chloride concentration and diffusion coefficients in concrete were analyzed.2.The deformation and failure characteristics of RC beams,as well as the mechanical properties of reinforcement were measured and analyzed.Combined with previous test results,the time-dependent model of the flexural bearing capacity of RC beams and mechanical properties of reinforcement were built.3.The uniform corrosion rate of reinforcement in RC beams was tested by weighing method.In addition,the time-dependent rule of the uniform corrosion rate of reinforcement,the initial corrosion time and the corrosion critical chloride ion concentration were analyzed.The sectional area of corroded reinforcement was acquired by the 3-D laser scanner and relevant reverse engineering related softwares.And then the nonuniformity of reinforcement corrosion was analyzed.4.On the basis of the previous test results,the calculation model of flexural bearing capacity of corroded reinforced RC beams were established.Besides,the modeling results were compared with the actually experimental results to confirm the viability of the presented models.