Several different healing agents and mechanisms have been put forward for use in autonomous healing of small cracks in cementitious composites. While the existing research on this topic focuses mainly on the use of polymeric materials as encapsulated healing agents,…
Several different healing agents and mechanisms have been put forward for use in autonomous healing of small cracks in cementitious composites. While the existing research on this topic focuses mainly on the use of polymeric materials as encapsulated healing agents, this study aims at assessing the efficiency of inorganic silica precursors as potential healing materials. This work investigated the effect on self-healing of different types of polymeric microcapsules containing silica precursors. The microcapsules were embedded in three different types of cement-based matrix, namely mortar, paste and grout. The results in all cases showed that the inclusion of microcapsules resulted in a marginal reduction of compressive strength in more cases for low volume fraction additions. Increasing the microcapsules concentration increased the reduction in the compressive strength. However, the observed crack healing % and durability recovery were substantially larger than any reduction on the mechanical properties. In addition, the incorporation of polymeric microcapsules in the cementitious matrix resulted in slight improvement of the composites’ fracture toughness.