Study On The Saturation And Transmission Of Chloride Ion In Concrete Under Dry And Wet Cycle

The research on the durability of concrete is a difficult and difficult point in the research of concrete.The nature of concrete is not only related to the material properties of concrete,but also related to external factors.About the durability of concrete,there are many aspects of research.China's coastline is very long,and there are wide areas of Saline Lake in the inland area.Chloride ion corrosion is one of the important problems,which often leads to accelerated corrosion of reinforcing bars inside concrete.Therefore,it directly affects the service life and maintenance cost of concrete.At present,the study of chloride corrosion and transport in concrete mainly focuses on two aspects: transport mechanism and experimental verification.In this paper,nine different dry and wet cycle experiments are designed.Through the experimental method,the factors affecting the transport of chlorine ion are analyzed and found,and the factors affecting the transmission of chlorine ion are found from the the aspects of saturation.The experimental study shows that the saturation of concrete increases slowly with time,and the saturation of concrete at different dry wet ratio is different,and the influence of dry wet system on concrete saturation is mainly influenced by the difference of dry wet ratio and dry wet cycle.The chloride concentration in concrete shows a certain regularity of time variation during the gradual increase of cycling period.The curves of chloride concentration changing with time show that the chloride concentration of concrete surface increases exponentially with time and becomes stable eventually.Different types of function fitting fit the time variation model of chloride concentration on the surface of different groups with the change of cycle,and the correlation of exponential function fitting and fitting curve are better.The values and ranges of convective and convective depths under differentdry and wet conditions are analyzed,and the time-varying model of the variation of convective peaks with periodicity is fitted.The law and mechanism of chloride ion transport in concrete are summarized.