Transmedia water migration characteristics of silty clay–concrete interface systems based on a fluorescent tracer

Transmedia migration of water is the key factor influencing the bond and shear mechanical properties of the interface system between soil and concrete. In numerous engineering projects, failures often occur at the soil–concrete interface, making the study of transmedia water migration in soil–concrete interface systems highly significant. This research based on the tracer properties of fluorescein to conduct a transmedia water infiltration test on silty clay–concrete interface systems. A fluorescent quantitative method was proposed to determine the moisture content within the concrete profile. The study investigated the migration of the wetting front, changes in water content, moisture distribution across the profiles of both media, and the spatial and temporal variations of soil moisture during the transmedia water migration process. The characteristics of transmedia water migration were compared under different initial soil water contents (IWC). Results demonstrated that the water distribution law of silty clay–concrete interface systems was not monotonous; notably, the water content in the interface area increased significantly. An increase in IWC inhibited the migration of the wetting front and the water content increment of the silty clay, while promoting the progression of saturation. Additionally, the water migration in the concrete was influenced by the silty clay. The proposed fluorescent quantitative method demonstrated high measurement accuracy.