Abstract: This paper presents the groundwater corrosion to the foundation element test results. The water samples are collected from three toll collection locations in TangLang Expressway: BL, YL and FJ. The groundwater at various sampling time were tested for its corrosion to the concrete and steel reinforcement bars. The sampling collection time effect on the water corrosion is also studied. The results indicate that, within the same site, the impact of sulfate contents, magnesium contents and total salinity on the concrete and steel corrosion do not change with time. The same conclusion can be extended to the chloride content on the corrosion of the concrete and the steel. It is also recommended and the drilling only with clean water should be used in order to have an accurate groundwater sampling.      

Key words: Groundwater, Corrosion, Time Effect, Concrete, Steel