应用丝束电极技术测量浸在10%NaC l溶液中的混凝土内铁丝束的自腐蚀电位和极化电阻分布,研究裂纹对混凝土中铁丝腐蚀的影响和乙醇胺的缓蚀作用.结果表明,裂纹加速了水、氧和氯离子向两侧混凝土中扩散,增加了铁丝腐蚀的不均匀性.乙醇胺扩散到混凝土中,吸附在铁丝表面,基本不改变铁丝的自腐蚀电位,但显著降低了铁丝腐蚀速率,有效抑制了裂纹引起的不均匀腐蚀.
The effects of crack and ethanolamine on corrosion of rebar in concrete were studied by measuring the distribution of corrosion potential and polarization resistance of iron wires in 10% NaCl solution.The results showed that the diffusion of water,oxygen and chloric ion toward concrete was accelerated by the crack which intensified the nonuniform corrosion of iron wire with the regions near to crack as anode and the uncracked regions as cathode.Ethanolamine could diffuse into the body of concrete and absorb on the surface of iron wire,which reduced iron corrosion evidently and successfully inhibited the nonuniform corrosion caused by crack without changing the corrosion potential.
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