Permeation and Transport Properties of Self-Healed Cementitious Composite Produced with MgO Expansive Agent

Abstract

This study evaluated the self-healing capability of engineered cementitious composite (ECC) produced with 5% MgO expansive agent (MEA) compared with standard ECC counterparts. The efficiency of the proposed ECC-MgO self-healing system was studied based on the rapid chloride ion permeability (RCP) and sorptivity behaviors of the virgin and cracked specimens when exposed to water, natural, and autoclave curing conditions for different durations. Test results indicated better resistance to chloride ion penetration in addition to significant reduction in sorptivity indexes (considered as measures of self-healing capability) for water- and natural-cured preloaded cracked ECC-MgO specimens compared with their ECC counterparts. The higher self-healing ability of ECC-MgO system was attributed to the formation of healing compounds within the crack walls due to the delayed MEA hydration, as confirmed from microstructural characterization based on scanning electron microscopic (SEM) analyses. The study revealed the potential of using the self-healing ECC-MgO system as sustainable and durable material for infrastructure applications.