The 4th Asian Concrete Federation Symposium on Emerging Technologies for Structural Longevity (ACF2023- ETSL)

77 / 2022-04-13 21:22:14

Chloride Penetration into Steam Cured Concrete at Tidal Zone

steam cured concrete,chloride,tidal zone,real marine environments

Steam curing as a main technical means to produce precast concrete elements is widely used in practical engineering. Chloride penetration is an important factor affecting the durability and safety of reinforced concrete structures in marine environments, especially in marine tidal zone where more severe corrosion occurs. The chloride penetration behavior and transport method based on experimental and theoretical analysis of steam curing concrete in the tidal zone were researched. The different types of steam curing concrete were exposed in real marine environments for 3-, 6- or 24-months, the chloride concentration distribution include free chloride and total chloride were obtained. The influences of types and dosages of mineral admixtures and exposure times for chloride ion diffusion coefficient and chloride ion binding capacity of steam curing and standard curing concrete were researched, and based on XRD, TGA, LF-NMR, ²⁹Si NMR and ²⁷Al NMR for future studies and observe. A theoretical prediction model about the time-dependence of chloride penetration and chloride ion binding capacity of concrete was established. It provides a theoretical reference for the long-life and long-life prediction of steam curing concrete structures in marine environment.