The effects of PE and PVA fiber and water cement ratio on chloride penetration and rebar corrosion protection performance of cracked SHCC

다국어 초록 (Multilingual Abstract)

<P><B>Abstract</B></P> <P>SHCC mixtures with various water cement ratios and different types of fiber (PVA and PE) were tested with an aim to clarify the properties of cracked SHCC. After examining the mechanical performances of the composites, chloride penetration and rebar corrosion tests were conducted on cracked SHCC specimens.</P> <P>PE fiber, PVA fiber, and a mixture of PE and PVA were added in SHCC. Part of the cement was replaced with limestone powder in some mixtures to vary the water cement ratio of the mortar matrix. For SHCC mixtures containing PVA fiber, which has lower strength and Young's modulus, the water cement ratio had to be increased to obtain a strain hardening property. The chloride penetration test revealed that chloride could penetrate into SHCC through fine cracks and that the width of the fine cracks had no bearing on the amount of chloride accumulated in the crack fracture surfaces. On the other hand, chloride penetration through cracks into the mortar matrix was affected by the number of cracks and water cement ratio. As a result, the corrosion area on rebar in cracked SHCC was also largely dependent on the number of cracks and water cement ratio. However, the corrosion area was smaller than that of ordinary mortar. When the strain is in a small range, the corrosion prevention performances of PE-SHCC and PVA-SHCC were more or less the same.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Rebar corrosion protection performances of cracked SHCCs were investigated. </LI> <LI> Chloride penetration through cracks into SHCC was affected by the number of cracks. </LI> <LI> It was also affected by W/C of mortar matrix. </LI> <LI> The corrosion prevention performances of PE-SHCC and PVA-SHCC were comparable. </LI> <LI> Even SHCC with low ductility can enhance the durability of RC structures. </LI> </UL> </P>