Synergistic Effect of OH-rich Fibers and Mineral Capsules on the Self-Healing Properties of Cement Mortar

Fibers and capsules are effective technologies for delaying the occurrence of cracks and improving the self-healing capacity of cement-based materials. In this study, OH-rich polyvinyl alcohol (PVA) and sisal fibers rich and mineral capsules containing healing agents (light burned MgO, carbide slag, and montmorillonite) were added to premixed cement mortar. Water permeability and crack healing area were used to clarify the contribution of each healing agent to crack healing and the synergistic effect of fibers and mineral capsules on healing of cracks in cement mortar. In addition, the optimal capsule content and characteristics of the healing products due to self-healing were also determined. The results show that the mechanical properties of cement mortar are improved when the mineral capsule content is 9%. Light burned MgO played a major role in crack healing and –OH in fibers also promoted self-healing of cracks. The healing process mainly produced calcite-type CaCO3, petal-like hydromagnesite, and dypingite.