Cl^(-)浓度对钢筋混凝土在土壤中腐蚀行为的影响

Influence of Cl^(-)Concentration on Corrosion Behavior of Reinforced Concrete in Soil

针对环境中Cl^(-)侵蚀钢筋混凝土构筑物造成混凝土及其内部钢筋结构发生破坏的问题,采用数值模拟的方式研究了Cl^(-)对钢筋混凝土腐蚀行为的影响。结果表明,钢筋混凝土在受到Cl^(-)侵蚀时,试件靠近侵蚀界面的位置Cl^(-)浓度较大;随着实验的进行,试件内部Cl^(-)含量不断增加,且钢筋表面Cl^(-)浓度差逐渐增大。混凝土试件内部的钢筋腐蚀深度与Cl^(-)含量相关,钢筋表面Cl^(-)浓度大的位置腐蚀较为严重。此外Cl^(-)浓度范围在100~600 mol/m^(3)之间时,Cl^(-)浓度与钢筋钝化时间T满足四次函数关系,与钢筋表面的电位E之间满足五次函数关系。

The influence of Cl^(-)on the corrosion behavior of reinforced concrete was studied by means of numerical simulation method,aiming at the troubles related with the chloride ion induced corrosion of reinforced concrete structure in the environment and the damages of the concrete,as well as the reinforced bars within the concrete.The results show that:when reinforced concrete is suffered from attack in a chloride ion containing environment,the chloride ion concentration is greater in the boundary layer near the concrete surface;as the experiment progresses,the chloride ion content inside the concrete increases,and the gradient of chloride ion concentration on the reinforced steel surface gradually increases.The corrosion depth of the steel bars in the concrete is related to the chloride ion content,and the corrosion is more serious in locations where the chloride ion concentration is high on the surface of the steel bars.In addition,when the Cl^(-)concentration range is between 100 and 600 mol/m^(3),the relationship between Cl^(-)concentration and passivation time T of the steel bar may accord with a quartic function,while a quintic function for relationship between the Cl^(-)concentration and the potential E of the steel bar surface.