ABSTRACT
ABSTRACT The paper reports on a study to use synthesised gelatin/acacia gum microcapsules as a carrier for spores and growth media for self-healing mortar. The microcapsules were created using complex coacervation. It was found that encapsulation of spores of Bacillus pseudofirmus was relatively straightforward. However, because elements of the growth media were water-soluble it was necessary to use an emulsion stabiliser to create suitable microcapsules. The microcapsules were added to cement mortars and pastes to investigate their effect on early-age properties and their self-healing capability. Isothermal conduction calorimetry showed that the microcapsules had few effects on the hydration of cement and that they survived the mixing process as designed. Tests were carried out to determine the self-healing capability by means of capillary absorption. Calcite precipitation and crack closure was observed in the mortar that contained both encapsulated spores and growth media.
