Microscopic mechanisms and chloride resistance performance of silane coupling agent self-assembly on reinforced concrete utilizing X-ray CT technology: A comprehensive investigation

To enhance corrosion resistance in reinforced concrete exposed to chloride environments, a gamma-aminopropyltriethoxysilane (KH550) solution was used to treat the steel bar surface. This study investigated the corrosion resistance and microscopic mechanism of self-assembled silane film modified steel bars. Surface morphology, elemental composition, and functional group changes were analyzed using SEM, EDS, and FTIR before and after solution treatment to determine the optimal treatment concentration. X-ray computed tomography (X-ray CT) was employed to analyze rust evolution and fracture characteristics in steel bars treated with silane coupling agent self-assembly technology. Results revealed that the self-assembly of molecules significantly enhanced corrosion resistance when using a water to ethanol to KH550 solution volume ratio of 50:3:10. The corrosion resistance mechanism of silane self-assembled steel bars against chloride salt corrosion was verified through X-ray CT technology, quantifying the volume expansion rate of rust products.