Investigation of corrosion assessment of hydrogen-rich water based cement mortars

Abstract

This study primarily investigates the effects of hydrogen-rich water (HRW) on the rebar corrosion embedded in Portland cement mortars. We comparatively assessed the performances of reinforced HRW-based mortars (HWMs) with respect to cement mortars fabricated from control water (CWM). The results indicate that the use of HRW significantly improves the anticorrosion properties of rebars embedded in cement mortars. Lower electronegative corrosion potential and the galvanic current were observed in HWMs compared to CWM. The electrical resistivity (ER) of HWMs was observed to be higher than those of CWM. Moreover, the HRW reduces the setting times and improves mechanical properties. The generally improved mechanical and anti-corrosion properties of HWMs are attributed to the formation of more cement hydrates with fewer voids in the hydrogen-rich environment. Based on X-ray diffraction (XRD), Fourier transform infrared (FTIR), and scanning electron microscope (SEM) analyses it was deduced that the use of HRW in Portland cement mortars produces a more compact, dense, and durable microstructure with fewer voids due to a higher degree of hydration. The higher degree of hydration in HRW leads to precipitation of greater amount of cement hydrates especially calcium hydroxide (Ca(OH)(2)) which helps maintain passive condition for reinforced bars.