氯盐侵蚀混凝土表层氯离子对流区深度和时变性能

Study on the convective depth and time-varying properties of chloride convection zone on concrete surface

为研究氯盐侵蚀环境中的混凝土表层氯离子分布及其对流区深度,分析混凝土内部水分影响深度和表层氯离子含量变化规律,建立混凝土表层氯离子对流区深度模型,研究滨海环境中的混凝土表层氯离子含量与高程、距海边距离和时间的关联度,推导出相应的混凝土表层氯离子含量的时空分布函数表达式。研究结果表明:氯盐侵蚀环境中的混凝土氯离子对流区深度与混凝土内部水分影响深度之间存在密切关联。氯盐环境中高程和距海距离对混凝土表层氯离子含量的影响可采用S曲线进行描述。混凝土表层氯离子最大含量随时间增加而增大,但最终趋于稳定。混凝土表层氯离子深度变化模型可准确揭示氯盐环境中的混凝土表面氯离子含量变化规律,可为预测混凝土表层氯离子含量分布提供参考。

The distribution and convective depth of chloride ions on the concrete surface under the chloride salt erosion environment were investigated,and the convective depth model of chloride ions on the concrete surface was proposed by analyzing the change of the water-influenced depth and chloride ion concentration.Simultaneously,the internal relationships of the chloride ion concentration on the concrete surface and the elevation,distance from the sea and time were also studied.Then,the corresponding spatial and temporal distribution function of chloride ion concentration on concrete surface was established.The results showed that there was a close correlation between the depth of the chloride convection zone of concrete in chloride salt erosion environments and the water-influenced depth in concrete.The relationship between the chloride ion concentration on the concrete surface and the elevation and distance from the sea can all be characterized by the S-curve.The maximum concentration of chloride ions on the concrete surface increased with the increase of time,but its value eventually tended to be a constant.The convective depth model of chloride ions on concrete surface can accurately present the change rule of concrete surface chloride ion concentration in chloride salt environment,which can provide a reference for predicting the distribution of concrete surface chloride ion concentration.