碳化与侵蚀耦合作用下混凝土氯离子传输机制研究

Study on Chloride Ion Transport Mechanism of Concrete under Coupling Action of Carbonation and Erosion

本文采用室内试验的研究方法,测定混凝土在碳化-侵蚀耦合作用下、不同温度以及不同侵蚀时间下的氯离子浓度分布与氯离子扩散系数,分析碳化-氯盐多因素耦合作用下混凝土的氯离子传输机理。研究表明:在距混凝土表面20mm的范围内,氯离子浓度有较大的增长,浓度与扩散系数均随着温度的升高而呈增大趋势;氯离子扩散系数随荷载的增加呈现增大趋势,且荷载比例越大,其增加的趋势越明显。研究成果可为沿海地区的混凝土结构耐久性问题提供参考依据。

In this paper,the chloride ion concentration distribution and chloride ion diffusion coefficient of concrete under the coupling action of carbonation and erosion,different temperatures and different erosion time are measured by laboratory test,and the chloride ion transport mechanism of concrete under the coupling action of carbonation and chloride salt is analyzed.The results show that:within the range of 20 mm away from the concrete surface,the chloride ion concentration increases greatly,and the concentration and diffusion coefficient increase with the increase of temperature;The chloride diffusion coefficient increases with the increase of load,and the larger the load proportion is,the more obvious the increase trend is.The research results can provide reference for the durability of concrete structures in coastal areas.