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 Portlandcement mortars. We comparatively assessed the performances of reinforced HRW-based mortars (HWMs) with respect tocement mortars fabricated from control water (CWM). The results indicate that the use of HRW significantly improves theanticorrosion properties of rebars embedded in cement mortars. Lower electronegative corrosion potential and the galvaniccurrent were observed in HWMs compared to CWM. The electrical resistivity (ER) of HWMs was observed to be higher thanthose of CWM. Moreover, the HRW reduces the setting times and improves mechanical properties. The generally improvedmechanical and anti-corrosion properties of HWMs are attributed to the formation of more cement hydrates with fewer voidsin the hydrogen-rich environment. Based on X-ray diffraction (XRD), Fourier transform infrared (FTIR), and scanningelectron microscope (SEM) analyses it was deduced that the use of HRW in Portland cement mortars produces a morecompact, dense, and durable microstructure with fewer voids due to a higher degree of hydration. The higher degree ofhydration in HRW leads to precipitation of greater amount of cement hydrates especially calcium hydroxide (Ca(OH)2) whichhelps maintain passive condition for reinforced bars.