Influence of Microfiber Additive Effect on the Self-healing Behavior of Engineered Cementitious Composites

This paper investigates the self-healing behavior of Polyvinyl Alcohol Engineered Cementitious Composites (PVA-ECC) with the addition of other microfibers, including steel fiber and rock wool fiber. Four-point bending tests were used to precrack ECC beams at the age of 7 and 28 days, respectively. The precracked samples were then cured in water to promote the occurrence of self-healing and in air for control. The addition of microfibers help tighten the crack width greatly, resulting in enhanced flexural stiffness for the water cured samples. Furthermore, the additive effect also promotes larger extent restoration of deflection capacity, despite much lower initial deflection capacity for the mixtures 2a and 3a. The self-healed samples were also examined under light microscope and environmental scanning electrical microscope (ESEM) to reveal the products of self-healing.